What happened
Matti Haapoja was a 19th-century Finnish criminal linked to multiple killings in Finland and during periods spent in the Russian Empire.
The investigation
His repeated escapes, arrests and changing accounts made it difficult for historical authorities to determine the exact number of victims attributable to him.
What the courts or investigators concluded
Haapoja was convicted of murder and other violent offenses and ultimately died in prison.
Why the case remains significant
The case belongs to an era before modern forensic policing and shows why victim counts for historical serial offenders should be treated cautiously when based on confessions, rumor and incomplete records.
Case context
Crime by Region organizes cases geographically so readers can move from one file to other investigations from the same country. For unresolved or contested cases, the wording above reflects the distinction between confirmed events, investigative theories and findings actually established in court.