Persian Warriors from the Berlin Museum.
Persian Warriors from the Berlin Museum. Source:

Assessing the reliability of sources evaluates whether they are trustworthy and yields credible information.


In the same way that it is rare to get sources that are 100% accurate, it is hard to be completely sure that sources are 100% reliable. Therefore, when we talk about reliability of sources, we can talk in terms of ‘degrees of reliability':


Extremely - Very – Somewhat – Rarely – Not very


To assess the reliability of a source, ask questions like:

Demonstrating source reliability in your writing:


This source is mostly reliable regarding factory conditions in the Industrial Revolution because the creator lived next to a major industrial facility during the 19th century.


Plutarch describes what happened, saying, “…”, but he often wrote to entertain so historians can’t always trust what he says (as found in Scott-Kilvert 1960, 76).


An overly romantic account is offered by Plutarch: “…” (as found in Scott-Kilvert 1960, 76)


John Smith, whose own personal experience as a soldier in World War I provides a highly reliable description on the living conditions in the trenches, says “…” (1981, 31).