The Hinterkaifeck Murders (1922): Six Killed With a Mattock on a Bavarian Farm.

What happened at Hinterkaifeck, in a paragraph.

Hinterkaifeck was a small farmstead set in a clearing in the woods approximately one kilometre from the village of Gröbern in Upper Bavaria, owned and worked by Andreas Gruber, a 63-year-old smallholder with a difficult local reputation. Living with him at the end of March 1922 were his wife Cäzilia (72), their widowed daughter Viktoria Gabriel (35) whose first husband had been killed in the First World War, Viktoria's two children Cäzilia (aged 7) and Josef (aged 2), and a newly arrived maid, Maria Baumgartner (44), who had taken up the position on the afternoon of March 31, 1922. The maid she replaced had given notice and left some six months earlier, telling acquaintances she believed the farm to be haunted. In the days leading up to March 31, Andreas Gruber had told neighbours and at least one priest of footprints he had found in the snow leading from the edge of the forest to the farm but not back, of a newspaper he did not recognize that had appeared on the property, of a set of house keys that had vanished, and of footsteps and other noises in the attic during the night. On Friday March 31, sometime after dark and presumably after Maria Baumgartner had arrived and unpacked, one or more assailants drew the four adults of the household into the barn one at a time and killed them with a mattock. The killer or killers then entered the house, found the child Cäzilia (7) asleep in the parlour and Maria Baumgartner asleep in the maid's room, and killed both with the same weapon. The toddler Josef (2) was killed in his crib in his mother's bedroom. The killer then remained on the property for an extended period — at minimum two and probably three full days — feeding the cattle, cooking food in the kitchen, and sleeping in one of the beds. On Tuesday April 4, four neighbouring farmers, alarmed that Cäzilia had not come to school all week, that the postman had not seen the family, and that the milking pail had been left out in the yard, walked to the property. They found the four adults stacked in the barn and the two children in their beds. The killer was gone. The mattock was found near or in the barn. A century of investigation has not produced a credible solitary suspect. The case file at the Schrobenhausen and Munich offices of the Bavarian State Criminal Police remains technically open.

The documented record.

The farm and the family

The Hinterkaifeck homestead consisted of a single combined house-and-barn structure under one long roof — a layout known in Bavarian rural architecture as an Einfirsthof — together with outbuildings, a small chapel, and an enclosed yard. Verified The property had been in Andreas Gruber's family for several generations. It was reachable by a single dirt track through woodland from the road to Gröbern, approximately one kilometre away. The farm was isolated, not part of any village.

Andreas Gruber (63 at his death) had a documented and substantial local reputation for personal cruelty. Verified Police records and parish-investigation documents compiled after the murders established that he had been twice charged with incest and serious physical abuse by his daughter Viktoria Gabriel during her adolescence and again after the death of her husband; one of those charges had been concluded with a short prison term [1][2]. Viktoria's daughter Cäzilia (7) was the recorded child of Viktoria and her late husband Karl Gabriel; her son Josef (2) had been born without a registered father and there was sustained village rumour, repeated in post-murder investigation, that Andreas was his biological father. Viktoria had at one point sought to marry a neighbour, Lorenz Schlittenbauer; that engagement had been broken off in 1921, with Schlittenbauer's later marriage and Viktoria's continued cohabitation with her parents the result. The community history of the family at the time of the murders is exceptionally well-documented because every neighbour and parish officer was interviewed in the weeks following [1][3].

The strange events of the preceding six months

Between approximately October 1921 and the end of March 1922, several incidents on the farm were later recalled by Andreas Gruber to neighbours and at least one priest (Father Andreas Haas of the parish of Waidhofen): Verified

• The previous maid. The maid employed at Hinterkaifeck before Maria Baumgartner gave notice in or about October 1921 and left, telling acquaintances that she believed the farm was haunted because of the sounds she heard at night [1][3].
• The newspaper. A copy of a newspaper that Andreas Gruber did not subscribe to and could not account for had appeared on the property in early 1922.
• The missing keys. The set of front-door keys to the farmhouse had gone missing in the weeks before the murders. Andreas Gruber had not had the locks changed.
• The footprints. Approximately a week before the murders, Andreas Gruber had reported finding footprints in the fresh snow leading from the edge of the forest to the house, but with no return tracks. He had searched the loft, sheds, and outbuildings but found nothing.
• The attic sounds. Andreas Gruber had told several individuals that he had heard footsteps and other sounds in the attic during the night. He had searched the attic; he had found no one.

The above accounts are recorded in police statements taken from neighbours and parishioners in April 1922 [1][3][4]. Andreas Gruber did not contact the police about any of the incidents and did not, by neighbouring testimony, take any defensive precautions. The accounts are second-hand reportage of statements Gruber had made; Gruber himself did not survive to be questioned. Claimed

March 31, 1922

Maria Baumgartner arrived at Hinterkaifeck on the afternoon of March 31, 1922, dropped off by her sister Therese at the edge of the road. She is the only person who is reliably known to have been on or near the farm between Andreas Gruber's last documented contact with a neighbour earlier in the day and the murders that evening [1]. The 7-year-old Cäzilia had attended school in Gröbern on March 31 and had returned home as usual; she did not appear at school on the following Monday or Tuesday and the schoolmistress had not been notified of the family's plans [1].

The discovery, April 4

On Tuesday April 4, 1922, four neighbours — the farmer Lorenz Schlittenbauer (Viktoria's former fiancé), the wagoner Michael Pöll, the farmer Jakob Sigl, and Andreas's brother Johann Gruber (an inhabitant of Gröbern) — walked to the farm together after concern over Cäzilia's school absences, the postman's report that mail had been uncollected, and the dawn milking not having been heard. Verified They entered the barn first. Stacked in the barn, partly covered with straw, were the bodies of Andreas Gruber, his wife Cäzilia, the daughter Viktoria, and the granddaughter Cäzilia. All had been killed by repeated blows to the head with a heavy, mattock-like agricultural tool. Viktoria's head had been beaten with such force that the skull was extensively fractured. The young Cäzilia, who had survived the initial blow long enough to pull out tufts of her own hair (later found in her hand), had died of her wounds while lying on the barn floor [4][5].

The neighbours then entered the house. In the maid's room they found Maria Baumgartner dead in her bed, again killed by mattock blows. In the bedroom shared by Viktoria and her son Josef, they found Josef dead in his crib, killed by the same instrument. Verified Schlittenbauer was first into the kitchen and the inner rooms; his behaviour in the discovery scene was later the subject of legal challenge (see below). The police were summoned. By the time officers from the Schrobenhausen gendarmerie arrived from a distance of approximately ten kilometres, the four neighbours and a number of other villagers had walked through the property.

The crime scene as preserved

The crime scene was not preserved in any modern forensic sense [5][6]. Disputed In the days between the murders and the discovery, dozens of villagers and the four discoverers had moved through both the barn and the farmhouse. The Munich criminal police (Kriminalpolizei) under Inspector Georg Reingruber arrived from Munich on April 5 and conducted what was, by the standards of the period, a serious but not exhaustive investigation [5][7]. The forensic work conducted included photographs of the bodies in situ in the barn; measurement of the wounds; recovery of the mattock (found in or near the barn, exact location varying between accounts); examination of the kitchen (where bread had been freshly cut and a meal evidently prepared in the previous days); and examination of the cow shed (the animals had been fed and watered, the cattle apparently milked). The autopsies were conducted on April 5 at Hinterkaifeck itself; the heads of the four adult victims were removed and sent to Munich for further examination, where they were misplaced during the upheaval of the Second World War and have not been recovered [5][6]. Verified The bodies were buried locally in the Waidhofen cemetery on April 8.

What the killer did on the property after the murders

The state of the farmstead at discovery on April 4 is one of the most-discussed features of the case. Verified The cattle had been fed in the days between the killings and the discovery; the household dog (which had been heard barking by Schlittenbauer or another villager on the previous Saturday night, April 1) was alive and tied in the barn; food had been cut and partially eaten in the kitchen; smoke had been seen rising from the chimney by two neighbours on April 1 and again on April 2. Wood had been cut and fires had been kept lit. One of the beds — not Maria Baumgartner's — appeared to have been slept in after the murders [4][6][7]. Whatever the killer's motive, the killer evidently did not flee the scene immediately after the killings. The killer was on the farm for at least 48 and probably 72 hours.

The weapon

The murder weapon was a heavy mattock (a Reuthaue or Kreuzhaue), a Bavarian agricultural tool with a flat blade on one side and a pointed pick on the other, mounted on a long wooden handle. Verified It was found at the scene — an instrument that ordinarily belonged on the property, and which the killer had not brought with them and had not removed. The 1922 forensic examination matched the head wounds to the mattock; the mattock was lost from police custody at some point in the subsequent decades [5][6]. The choice of an on-site weapon and its leaving behind have been read as suggesting either a killer who improvised on the premises (an unfamiliar intruder taking what was to hand) or one for whom carrying the weapon would have been more incriminating than leaving it (a near neighbour). Both readings are defensible on the surviving record.

The 1922 investigation and Schlittenbauer

Lorenz Schlittenbauer, the neighbour and Viktoria's former fiancé, was the longest-investigated of the contemporary suspects. Verified His behaviour at the discovery scene was noted by other witnesses as composed; he moved through the property and rearranged some of the bodies (he later said he was searching for survivors); he had had a documented and contentious history with Viktoria, including a paternity dispute over the toddler Josef (Schlittenbauer had been ordered to pay support in 1919 on a claim of paternity that he disputed and that was later partially set aside) [3][8]. He was interviewed extensively, sued newspaper editors who had named him as a suspect, and was never charged. He died in 1941. Disputed The Bavarian State Criminal Police's 1955 internal review accepted that Schlittenbauer's behaviour at the scene was suggestive but found insufficient evidence to charge.

Other contemporary suspects investigated and not charged included travelling labourers, demobilized soldiers from the First World War who were known to be moving through the rural districts of Bavaria in unprecedented numbers in 1922, and members of an extended Gruber-family circle. The 1922 investigation produced more than 100 suspects [6][9]; none was ever charged. The case was set aside as inactive by the Schrobenhausen police in late 1923. The Bavarian State Criminal Police's Munich office produced a consolidated review file in 1955 and again in 1986, with no new arrests resulting.

The 2007 Polizeifachhochschule review

In 2007, the case was assigned as a teaching exercise to the cadets of the Bavarian Polizeifachhochschule (Police Academy) in Fürstenfeldbruck under Professor Albert Gauland and homicide investigator Konrad Mueller [10]. Verified The cadets reviewed the surviving case file, conducted background research on contemporary suspects, and at the conclusion of the exercise privately named one individual as their leading candidate. Out of respect for that individual's surviving family (the named individual's descendants live in the area), the cadets and the academy chose not to publish the name. The exercise did not produce sufficient evidence to support a posthumous charge, and the case was not formally resolved. The 2007 exercise has been cited in some accounts as a "solution" to the case; the academy's own statements describe it as a teaching exercise that produced a probable candidate but not a forensically demonstrable conclusion. Disputed

The 2017–2018 reopening

In 2017–2018, the Bavarian State Criminal Police (Landeskriminalamt) again reviewed the file in conjunction with documentary makers and the heirs of one of the suspects, but did not announce new findings. The case file at the Munich LKA remains technically open. Verified [11]

The competing explanations.

The Schlittenbauer hypothesis

The longest-standing and most-discussed hypothesis is that Lorenz Schlittenbauer himself, or in concert with another, killed the family. Claimed The evidentiary basis: Schlittenbauer's prior contentious relationship with the family; his disputed paternity of Josef and his ongoing financial obligation as a result; his familiarity with the layout of the farm; his unusual behaviour at the discovery scene; and his composed demeanour at a moment that distressed the other discoverers. Against the hypothesis: Schlittenbauer had no motive that the 1922 investigators could establish for killing the maid, who had arrived on the property only that afternoon, or for killing the children other than Josef; his alibi for the night of March 31 was credible if not unimpeachable; and the 1955 review concluded that the evidence was insufficient. He was never charged. The Schlittenbauer hypothesis remains the modal hypothesis in the secondary literature [8][9].

The Karl Gabriel hypothesis

Karl Gabriel, Viktoria's first husband, was officially reported killed at the front in France in December 1914. Claimed No remains were recovered to be returned to the family; the official death notice was based on his unit's report. One persistent line of speculation, traceable in the literature to publications of the 1950s, is that Karl Gabriel had survived the war, deserted or otherwise become detached from his unit, and returned to Bavaria in 1921–1922 to find his wife in a continuing relationship with her father and with a young son not his own. A Soviet prisoner-of-war repatriation list in the 1950s was once thought to suggest Karl Gabriel had been in Russian captivity, but the identification was later judged unsupported [9][12]. The hypothesis fits the "footprints to but not from the house" detail and the killer's familiarity with the property. It does not fit the 1914 death notice in its conventional reading; it requires an additional layer of speculation. Disputed

The robbery hypothesis

The 1922 investigators initially considered robbery, on the basis of the unusually large amount of cash sometimes kept on the property and on the known transient population in post-war Bavaria. Claimed A substantial cash hoard in the farm was, by Andreas Gruber's prior statements to neighbours, in the house; whether it was taken cannot be determined from the surviving record because no inventory of the property's cash holdings was available [4][5]. Against the hypothesis: the killer remained on the property for two-to-three days, an extraordinarily long time for a robber; the cattle were fed; the kitchen was used; an ordinary robbery does not account for the prolonged occupation.

The intruder-in-the-attic hypothesis

The detail most haunting to subsequent commentators is Andreas Gruber's pre-murder report of footsteps in the attic. Disputed A literal reading of that account — that the killer had been living concealed in the loft for weeks or months before the killings — would explain the missing keys, the unknown newspaper, the strange footprints, the lack of a forced entry, and the killer's familiarity with the property and the daily routine of the household. The hypothesis has the structural property of being consistent with most of the otherwise-inexplicable details. It also has the property of being entirely undocumented: no one was found in the attic, no contemporary trace of an attic occupant has ever been produced, and the post-murder examination of the attic did not produce material that established the presence of an unknown person. As a hypothesis it is parsimonious; as evidence it is absent.

The unanswered questions.

The identity of the killer

No one has been charged with the Hinterkaifeck murders. Unverified The 2007 police academy exercise produced a probable candidate that has not been publicly named or formally pursued. The case file at the Munich LKA contains, as of 2018, the most complete review the German police have made; that review has not produced an arrest.

The missing skulls

The skulls of the four adult victims, removed for laboratory examination in April 1922 and sent to Munich, were lost in the late stages of the Second World War, when the building housing the institute of forensic medicine in Munich sustained bombing damage [6][13]. Disputed The skulls would, if recovered, permit modern reanalysis of the wound patterns. Their loss forecloses one of the few avenues for modern forensic reassessment.

The previous maid

The unnamed maid who left Hinterkaifeck in late 1921 telling acquaintances the farm was haunted has not been definitively identified in subsequent research, in part because farm-maid positions in rural Bavaria were ordinarily filled through informal channels and not registered. Unverified Her testimony, if it could be recovered, might bear on the question of what the household had been experiencing in the months before the murders.

The motive for the maid

The killing of Maria Baumgartner is the part of the crime that fits least into any of the leading hypotheses [6]. She had been on the farm for less than a day; she had no documented connection to any of the suspects; she had no inheritance, no romantic entanglement with anyone, and no plausible standing relationship to a killer with a personal motive against the Grubers. Her presence at the scene therefore implies either that her killing was incidental to the killing of the family (the killer killed her because she was there and would have been a witness), or that the killer did not in fact know she had arrived (she had been delivered to the farm only that afternoon) and was surprised to find her there. Either reading is consistent with the surviving record.

The keys and the newspaper and the footprints

The specific pre-murder anomalies reported by Andreas Gruber — the missing keys, the unknown newspaper, the snow-print track, the attic footsteps — would, if they had been investigated contemporaneously, have produced testable evidence. Unverified They were reported by Gruber as recollections to neighbours; they were not investigated by police until after the killings; and the physical evidence of the prints, the keys, and the paper had largely been overwritten or removed by the discovery and the subsequent village traffic across the property. They remain unfalsifiable elements of the case.

Primary material.

• The Schrobenhausen gendarmerie investigation file (April 1922 onward), transferred to the Munich Kriminalpolizei in 1922 and consolidated into a Bavarian State Criminal Police case file at the LKA Munich.
• The Waidhofen parish records, including baptism, marriage, and burial entries for the Gruber family.
• Period press accounts: the Münchener Neueste Nachrichten, the Augsburger Postzeitung, the Schrobenhausener Tagblatt, all April–June 1922.
• Photographs of the discovery scene by the Munich Kriminalpolizei photographer (period name uncertain in surviving records), April 5, 1922. The photographs include the bodies in situ in the barn and the kitchen as found.
• The 1955 Bavarian State Criminal Police consolidated review, internal document, summarized for the public in a 1955 press briefing.
• The 1986 reopening file, internal LKA Munich.
• The 2007 Polizeifachhochschule Fürstenfeldbruck cadet exercise report, partial public summary published 2007.
• The 2017–2018 LKA Munich review file, internal, not publicly released.

The farmhouse itself was demolished in 1923, less than a year after the murders, on order of the Bavarian authorities and at the request of the local community, and the materials reused on neighbouring farms. The site is marked by a small shrine in the Hinterkaifeck clearing.

The sequence.

1. 1914 Karl Gabriel, Viktoria Gabriel's first husband, officially reported killed at the front. No remains returned.
2. 1915–1919 Viktoria Gabriel lives at Hinterkaifeck with her parents and infant daughter Cäzilia.
3. 1919 Birth of Josef. Paternity disputed; Lorenz Schlittenbauer ordered to pay support.
4. October 1921 The Gruber family's previous maid gives notice and leaves, reportedly stating the farm is haunted.
5. February–March 1922 Andreas Gruber tells neighbours of strange events on the farm: footprints in the snow, missing house keys, an unknown newspaper, sounds in the attic.
6. March 31, 1922 (afternoon) Maria Baumgartner, the new maid, arrives at Hinterkaifeck.
7. March 31, 1922 (evening) The six victims are killed, four in the barn with a mattock, two indoors with the same weapon.
8. April 1, 1922 Smoke seen rising from the Hinterkaifeck chimney by neighbours. Postman finds mail uncollected.
9. April 2, 1922 Continued absence noted by villagers; smoke again seen from the chimney.
10. April 4, 1922 Lorenz Schlittenbauer, Michael Pöll, Jakob Sigl, and Johann Gruber walk to the farm. The bodies are discovered.
11. April 5, 1922 Inspector Georg Reingruber and the Munich Kriminalpolizei arrive. Autopsies conducted at the farmhouse. Skulls of the four adults removed for examination at Munich.
12. April 8, 1922 Burials at the Waidhofen cemetery.
13. 1923 The farmhouse is demolished.
14. 1925–1955 Investigation periodically reactivated. More than 100 suspects examined; none charged.
15. 1941 Death of Lorenz Schlittenbauer.
16. 1944–1945 The skulls held at Munich are lost in the upheaval of the war.
17. 1955 Bavarian State Criminal Police produce a consolidated review file. No new arrests.
18. 1986 Case reopened by the Bavarian LKA. No arrests.
19. 2007 Polizeifachhochschule Fürstenfeldbruck cadet exercise. A candidate is named privately; no public identification.
20. 2017–2018 LKA Munich review. No new findings publicly announced.

Cases on this archive that connect.

The Dyatlov Pass Incident (1959) — another case in which the physical evidence is substantial but the investigative conclusions remain irreconcilable a generation later. Both cases share the structural property of an unexplained period of physical activity at the scene that the leading natural-causes (or solitary-intruder) hypothesis does not fully account for.

The Somerton Man (1948) — the Adelaide case of an unidentified man whose identity took 74 years to establish through DNA genealogy. Hinterkaifeck has not been amenable to the same approach because no skeletal material remains in police custody.

Planned: the Bavarian Kuderna case (1932); the Villisca axe murders (Iowa, 1912); the Keddie cabin murders (California, 1981) — all cases of multiple homicide by a heavy-edge weapon left at the scene and with no charge resulting.

Full bibliography.

1. Schrobenhausen gendarmerie report, April 4–15, 1922. Bavarian State Criminal Police archive, Munich.
2. Parish records, Waidhofen, Schrobenhausen district. Baptism, marriage, and burial entries for Andreas, Cäzilia, Viktoria, the children Cäzilia and Josef.
3. Witness statements collected by the Schrobenhausen gendarmerie, April 1922. LKA Munich case file.
4. Reingruber, Georg. Munich Kriminalpolizei lead investigator's notes, April–May 1922.
5. Autopsy reports of Andreas, Cäzilia, Viktoria, the granddaughter Cäzilia, Josef, and Maria Baumgartner. Held in the 1922 case file.
6. Bavarian State Criminal Police (LKA), consolidated review of the Hinterkaifeck case, 1955. Internal document with a press summary released to the German news agencies.
7. Pötzl, Norbert F. Hinterkaifeck: Spürensuche nach einem mysteriösen Mörder, Piper Verlag, 1997.
8. Edmaier, Manfred. Hinterkaifeck: Eine Wahre Geschichte, Allitera Verlag, 2007.
9. Kotting, Peter (ed.). Hinterkaifeck: Die Akten, edition Kröner, 2008. A compilation of public-record material.
10. Bavarian Polizeifachhochschule Fürstenfeldbruck, cadet exercise summary, 2007.
11. Bavarian State Criminal Police press statements on the case, 2017 and 2018. LKA Munich.
12. Hetzel, Andreas. Das Karl-Gabriel-Rätsel, in Bayerische Heimat, 1956. The first published treatment of the Karl Gabriel survival hypothesis.
13. Institut für Rechtsmedizin der Universität München, internal records on the war-period loss of skeletal material, 1944–1945.
14. Schlüter, Dieter. Der Hinterkaifeck-Fall: Versuch einer Chronologie, self-published in Schrobenhausen, 1981.
15. Bayerischer Rundfunk, documentary "Das Rätsel von Hinterkaifeck," 2017. Producer interviews with LKA Munich officers.