From Wildermyth Wiki

Also called History Line.

A line of player-facing text that tells a story about the entity it’s pinned to; can add and remove aspects, stat-increases, hooks; some is generated upon initialization, some is recorded in recognition of game-occurrences.

Hero History is generated at the start of the game with three lines: an Origin, and Anecdote, and a Motivation. These affect prime stats and personality stats, and also seed Hooks. History lines leave behind a number of Hooks, which are more specific character aspects and often take the form of a personality flaw or quirk.

Note that History lines cannot be queried, but can apply aspects, which can be queried.

(For a more general overview of how history relates to other parts of Wildermyth, see the Data Format Overview)