A member of the single Protestant family in the area, he moved first to Sligo, then emigrated to Frederick County, Maryland between 1760 and 1766. He began preaching in Maryland soon after his arrival, making him the pioneer of Methodism on the American continent. According to the 1801 Journal of Bishop Francis Asbury, Strawbridge founded "the first class (of Methodism) in Maryland and America" in 1768 at his log cabin near New Windsor. Little is known about Strawbridge's wife, Elizabeth Piper, although Strawbridge began his preaching tours soon after completing their log dwelling leaving wife and children on their rented 50-acre (200,000 m2) farm at Pipe Creek.
Preaching in his log cabin home and quickly organizing Methodist societies in the area, he helped establish the very earliest Methodist societies in North America. During these early years, Strawbridge also built log meeting houses at Sam's Creek and Bush near Aberdeen. He soon began travelling and preaching in Maryland, Pennsylvania, and Virginia, establishing a number of societies. He was very popular and had a major influence on many young preachers.
At the first recorded Quarterly Conference in Joppa in December 1772, Bishop Asbury formally appointed Robert Strawbridge and Richard Owings to the Frederick County circuit. Most likely always a layperson, he was criticized for administering the sacraments. The 1773 conference of Methodist preachers in America prohibited such preachers from such rites, except Strawbridge, and only then at the direction of Bishop Francis Asbury, who had been sent to the colonies by John Wesley to oversee the faith. Strawbridge was known to have continued even without Asbury.
Both New York and Maryland claimed the birthplace of American Methodism, in a dispute lasting more than 150 years. At the 1860 Baltimore Conference, Maryland was outvoted and the Centennial of American Methodism was celebrated in 1866, the year Methodism was founded in New York. However, it was later discovered that a Methodist minister in Ohio in 1813 had met a German farmer who claimed to have been converted by Strawbridge in Maryland in 1763. This evidence figured in a 1916 church decision that the origin of American Methodism was in Maryland, not New York.
- "Robert Strawbridge House near New Windsor, Maryland". The United Methodist Church - General Commission on Archives and History. Retrieved 2008-06-25.
- "History of Dumbarton Church". Dumbarton United Methodist Church Cookbook. Retrieved 2008-06-25.[dead link]
- "The Strawbridge Shrine". Strawbridge Shrine website. Retrieved 2008-06-25.