Lawrence Washington entered military service in 1740 as a captain in the Virginia companies raised for Britain's war against Spain. He served in the Caribbean expedition associated with Admiral Edward Vernon, including the unsuccessful attack on Cartagena in 1741. Returning to Virginia in 1742, he became a militia major and adjutant for the colony's northern district, carrying his experience of imperial warfare into local military administration. After inheriting Little Hunting Creek in 1743, Washington renamed the plantation Mount Vernon in the admiral's honor. He sought medical advice in England and traveled with George to Barbados in 1751, then went on to Bermuda before returning home in 1752. Tuberculosis increasingly interrupted his own activities. Upon his return to Virginia at the end of 1742, Washington discovered that the post of militia commander, Adjutant, was vacant. He applied for it and was appointed Adjutant, at the rank of Major, by Governor Gooch in Spring 1743. During the legislative session of 1748–49, Washington had the role of promoting the river site and securing the votes necessary to approve a new town on the Potomac, where it would best serve the interests of the Ohio Company. Washington was granted permission to "be absent from the Service of the House, for the Recovery of his Health." Prior to the first public auction of town lots in July 1749, Washington sailed to London to conduct business on behalf of the Ohio Company, and to consult English physicians regarding his health. Lawrence Washington died on Jul 26, 1752, in Fairfax County, Virginia.