Abigail Adams wrote her most celebrated letter in the spring of 1776 to husband John, then attending the Continental Congress in Philadelphia. In this letter, Abigail urges John to "Remember the ladies" and protect women's rights in the new American government. John was in the midst of formulating his ideas about the types of governments to be organized in the former colonies and in April published his essay Thoughts on Government. In Massachusetts, the British evacuation of Boston on 17 March freed American minds to contemplate their future, government, America's relations with foreign powers, slavery, and the status of women.