Complex sentence: This group founded the "Research Council on Problems of Alcohol" or the RCPA, which was an organization similar to Alcoholics Anonymous and soon after it was created, Bowman became a leader of this organization.
Split into simpler sentences: This group founded the "Research Council on Problems of Alcohol" or the RCPA, which was an organization similar to Alcoholics Anonymous. Soon after it was created, Bowman became a leader of this organization.