In the U.S., in 1907 Ana Jarvis, from Philadelphia, began a campaign to establish a national Mother's Day. Jarvis persuaded her mother's church in Grafton, West Virginia to celebrate Mother's Day on the second anniversary of her mother's death, the 2nd Sunday of May. The next year Mother's Day was also celebrated in Philadelphia.
Jarvis and others began a letter-writing campaign to ministers, businessmen, and politicians in their quest to establish a national Mother's Day. They were successful. President Woodrow Wilson, in 1914, made the official announcement proclaiming Mother's Day a national observance that was to be held each year on the 2nd Sunday of May.
Many other countries of the world celebrate their own Mother's Day at different times throughout the year. Denmark, Finland, Italy, Turkey, Australia, and Belgium celebrate Mother's Day on the second Sunday in May, as in the U.S.