Jeremiah Crabb—whose surname is sometimes spelled Crabbe and appears in this database as “Crab”—was born in Maryland in 1760, probably in the portion of Frederick County that later became Montgomery County. He was a son of Henry Wright Crabb. Surviving standard biographies say very little about his mother, siblings, schooling, or childhood household, and the available evidence does not justify reconstructing those details. He grew up in a rural region northwest of the Chesapeake tobacco ports, where farms, small mills, roads, and county courts connected inland communities to the wider provincial economy.

Crabb was still a child when resistance to British taxation intensified and only about fifteen when armed conflict began in 1775. Whatever formal education he received, he acquired sufficient literacy, social standing, and local confidence to obtain a commission in Maryland’s Continental forces while still very young. Officer appointments usually depended upon a mixture of ability, reputation, family connections, and the support of influential men. Crabb’s later career suggests that he belonged to a family capable of placing him within those networks, but the precise route to his commission is not preserved in the concise official record.

He entered the First Maryland Regiment as a second lieutenant. Maryland’s Continental troops developed a reputation for discipline and hard fighting, and a junior officer was expected to maintain order, transmit commands, supervise camp duties, and lead soldiers under fire. Crabb’s military education was therefore immediate and severe. He was promoted to first lieutenant on December 15, 1777, a sign that his superiors considered his service satisfactory.

The winter encampment at Valley Forge in 1777–1778 tested the army with cold, inadequate clothing, poor shelter, disease, and shortages. Crabb’s health deteriorated under those conditions. Although George Washington reportedly regarded his service favorably, illness forced the young lieutenant to resign on April 1, 1778. That resignation closes the formative phase of his life: by eighteen he had already experienced provincial Maryland, revolution, commissioned responsibility, promotion, and the physical hardships of the Continental Army. These experiences later underpinned his authority as a militia officer and politician.