is a German historian

Historian

A historian is a person who studies and writes about the past and is regarded as an authority on it. Historians are concerned with the continuous, methodical narrative and research of past events as relating to the human race; as well as the study of all history in time. If the individual is...

, specializing in the military history of World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, the German occupation of Poland 1939-1945 and the research on the perpetrators of the Holocaust.

Böhler obtained a Magister's degree

Magister (degree)

Magister is an academic degree used in various systems of higher education.-Argentina:...

 at University of Cologne

University of Cologne

The University of Cologne is one of the oldest universities in Europe and, with over 44,000 students, one of the largest universities in Germany. The university is part of the Deutsche Forschungsgemeinschaft, an association of Germany's leading research universities...

 in 1999, where he specialized in modern

Modern history

Modern history, or the modern era, describes the historical timeline after the Middle Ages. Modern history can be further broken down into the early modern period and the late modern period after the French Revolution and the Industrial Revolution...

 and medieval history, as well as ethnology

Ethnology

Ethnology is the branch of anthropology that compares and analyzes the origins, distribution, technology, religion, language, and social structure of the ethnic, racial, and/or national divisions of humanity.-Scientific discipline:Compared to ethnography, the study of single groups through direct...

 and political economy

Political economy

Political economy originally was the term for studying production, buying, and selling, and their relations with law, custom, and government, as well as with the distribution of national income and wealth, including through the budget process. Political economy originated in moral philosophy...

. His Magisterial thesis, Wehrmacht war crimes in Poland, won a departmental award. His PhD was finished at the same university in 2004.

He is a member of the German Committee for the History of the Second World War and of the Working Group on Military History. From 2000 on he has worked in the German Historical Institute

German Historical Institute

German Historical Institute are five independent academic research institutes situated in Rome, London, Washington, D.C., Warsaw and Moscow, dedicated to the study of historical relations between Germany and the host countries in which they are based, along with four other institutions, in Paris,...

 in Warsaw. Between 2003 and 2004 he was a Fellow in Residence at the United States Holocaust Memorial Museum.