author
1857–1937
A noted American medieval historian, he helped make European history more approachable through clear textbooks and carefully chosen source collections. He is especially remembered for editing the multi-volume Library of Original Sources.

by Oliver J. (Oliver Joseph) Thatcher, Edgar Holmes McNeal
Born in 1857 and active as an American historian, Oliver J. Thatcher focused on the Middle Ages and wrote for readers who wanted a solid, readable introduction to European history. Reliable library and reference records identify him as Oliver Joseph Thatcher and place his life from 1857 to 1937.
His work includes A Short History of Mediæval Europe, Europe in the Middle Age, and A General History of Europe (350–1900), along with A Source Book for Mediæval History. These titles show the range of his writing: both narrative history and collections of original documents intended to help students and general readers engage directly with the past.
Thatcher is also remembered as the editor of the multi-volume Library of Original Sources, a large documentary series built around influential historical texts. That editorial work fits the role he is best known for today: a scholar who helped open medieval and European history to a wider audience through accessible, source-based learning.