A member of Harvard's Class of 1871, William Lawrence was President Lowell's first cousin once removed. Ordained by the Episcopal Church in 1875, he served first in Lawrence, Massachusetts—named for his grandfather, who founded that city's textile mills—and later in Cambridge. He was elected bishop of the Diocese of Massachusetts in 1893.

Throughout, he maintained close ties to Harvard. From 1899 to 1908, he was vice president of the Harvard Alumni Association; he was an Overseer of the University from 1894 to 1906, and again from 1907 through 1913. In 1913 he was elected a Fellow and Member of the Harvard Corporation.

Meanwhile, he served various causes as an unparalleled fundraiser. In 1904, for example, he headed a drive for $2.5 million to increase Harvard College teachers' salaries; in 1914, he helped raise $2 million for Wellesley College when its main building burned to the ground. Between 1915 and 1917, he collected more than $8.5 million in a national drive to create and endow an Episcopal Church pension fund. After World War I, he raised $1 million to endow Cambridge's Episcopal Theological School.

"You strike what is called a deep pool," Lawrence wrote in an Atlantic Monthly article describing his fundraising experiences. "No fish rises, and you go back to camp depressed. You cast into a shallow and almost hopeless pool, and come away with big game. You have all the fun of the gambler, and do not gamble."