Father's Day is a celebration honoring fathers and celebrating fatherhood, paternal bonds, and the influence of fathers in society. The tradition was said to be started from a memorial service held for a large group of men who died in a mining accident in Monongah, West Virginia in 1907. It was first proposed by Sonora Dodd of Spokane, Washington in 1909. It is currently celebrated in the United States annually on the third Sunday in June.

When was father's day started in the us? OK. Let's think. My stream of consciousness:
The relevant sentence in the passage is: The tradition was said to be started from a memorial service held for a large group of men who died in a mining accident in Monongah, West Virginia in 1907. The answer is 1907.