 As tensions rose between the British parliament and the colonies, he gradually adopted positions in opposition to the parliament's policies.When the American Revolutionary War broke out in April 1775, Washington arrived at the Second Continental Congress in a military uniform, and was chosen as Commander-in-chief of the Continental Army.After leading American forces to victory, he chaired the Constitutional Convention that drafted the United States Constitution, and was then elected the first President of the United States, serving two terms.