AHC: At least 3 million Samaritans in 1899

An ethnoreligious group descended from the ancient Israelites, the Samaritans (or Shamerin, as they call themselves) consider their faith of Samaritanism to be the true religion of their ancestors. While there were once many Samaritans, today they number less than a thousand, with the majority of the population concentrated in Israel and the State of Palestine, though there are also small populations in Brazil and Sicily.

Your challenge is to have there be at least 3 million Samaritans alive in the year 1899. You may use any point of divergence you want.