Thanks to a Leeward Press reader for pointing out that this building is actually an old mission. I ran across it on my last trip to Pelee, and was curious about its origins.
According to Noah Garno's The Story of Pelee, which he wrote in the 1950s, the structure was built by George E. Pegg, who moved to Pelee from Pennsylvania in 1891.
Pegg lived in what was then called the Middle Island section of Pelee, which is, as you'd expect, near the island's centre. Seeing that there was no church or Sunday school in the area, Pegg, with the help of local citizens, built the mission in 1911.
Here's what Garno wrote of Pegg: "For many years Mr. Pegg taught school at Middle Island, in fact until 1932. He audited books and kept records for the Pelee Co-operative Association for several years, and also was treasurer for the Township of Pelee from 1914 until 1945. Mr. Pegg was always ready with kind advice; and many will not forget Mrs. Pegg, as she took care of the sick and was ready at all times to tend to the needy."