Throughout the 18th century, Enlightenment ideas of the power of reason and free will became widespread among Congregationalist ministers, putting those ministers and their congregations in tension with more traditionalist, Calvinist parties.:1–4 When the Hollis Professor of Divinity David Tappan died in 1803 and the president of Harvard Joseph Willard died a year later, in 1804, a struggle broke out over their replacements. Henry Ware was elected to the chair in 1805, and the liberal Samuel Webber was appointed to the presidency of Harvard two years later, which signaled the changing of the tide from the dominance of traditional ideas at Harvard to the dominance of liberal, Arminian ideas (defined by traditionalists as Unitarian ideas).:4–5:24