Short answers, pulled from the story.
Frank Mentzer was born in Springfield, Pennsylvania, and grew up in a family deeply connected to the National Park Service. He graduated from Springfield High School in 1968 before attending West Virginia Wesleyan College and later Northeastern University to study mathematics and physics.
Frank Mentzer won TSR's first DM Invitational in 1980, receiving a silver cup and a gold dragon chain of office. This victory marked his entry into the game design industry after he had taught himself Dungeons & Dragons in the mid-1970s with a group of eight to twelve players.
Frank Mentzer released the third edition of the Basic Set in 1983, which spawned five boxed sets known collectively as BECMI. He meticulously collated and revised the rules to create a self-contained system that did not borrow material from Advanced Dungeons & Dragons, allowing characters to advance from first level to godhood.
Frank Mentzer left TSR in 1986 because he was unwilling to work for chairman Lorraine Williams after Gary Gygax was ousted at the end of 1985. His departure reflected his loyalty to Gygax and his belief in the direction they had been taking together during their six years of collaboration.
Frank Mentzer and his second wife Debbie opened a bakery in Minocqua, Wisconsin, in 2000, which eventually expanded to include three bakeries. He managed the operation until 2008 when the decision was made to shut down the bakeries and move to Rockford, Illinois.
Frank Mentzer announced the formation of Eldritch Enterprises in November 2010, and the company was incorporated in April 2011. The company focused on publishing general works, children's books, baking books, and hobby game projects centered on Old School roleplaying systems such as the original D&D rule set and Metamorphosis Alpha.