The Newt Gingrich file

Newt Gingrich, the former Georgia congressman and one-time U.S. House speaker, once believed to be on Donald Trump's short list of potential running mates, is now among his critics. Read more about Gingrich and Trump

Here are 18 things to know about Gingrich:

1. Born: Newton Leroy McPherson, June 17, 1943, Harrisburg, Pa. Changed his name to Gingrich after he was adopted by his stepfather.

2. His first civic act as a young boy was lobbying the city of Harrisburg to open a zoo, and his zeal for animals continues to this day — including memorable detours from the presidential campaign trail.

3. Childhood: Army brat living in the U.S. and Europe before graduating from high school in Columbus, Ga.

4. First wife: Jacqueline Battley Gingrich, Newt’s high school math teacher and mother of his children.

5. Second wife: Marianne Ginther Gingrich, a political fundraiser from Ohio for whom Newt left Jacqueline.

6. Current wife: Callista Bisek Gingrich, with whom Gingrich carried on a lengthy affair while she worked as a congressional staffer. She is now the author of a popular series of childrens books.

7. Children: Jackie Gingrich Cushman, commentator, author and charity entrepreneur; Kathy Gingrich Lubbers, a business consultant

8. Religion: Roman Catholic (he converted after marrying Callista)

9. As a history professor at West Georgia College in Carrollton, he was first elected to the U.S. House in 1978 after two failed attempts.

10. Moved to Marietta to run for re-election in 1992 after Gold Dome Democrats drew him out of his west Georgia district.

11. Credited with stoking the rise in negative partisanship because of his relentless personal attacks on Democrats — including ethics charges against then-Speaker Jim Wright — to help him build the GOP and eventually earn the historic 1994 takeover. Ahead of the 1994 election, Gingrich helped devise the “Contract with America,” a list of 10 bills — including a balanced budget amendment, a measure calling for term limits and an anti-crime package — and eight changes in congressional process the GOP vowed to address if it took over. After Republicans’ historic landslide brought them into power, the House passed most of the contract planks, but few became law.

12. Encouraged lawmakers to live at home instead of in Washington to be closer to their constituents, helping create Congress’ current “don’t linger” culture that many analysts say precludes bipartisanship.

13. In 1997 the House Ethics Committee voted to fine him $300,000 (the first speaker to be so punished) for misleading the committee about political donations connected to his college video lecture course.

14. Was occasionally portrayed by actor Chris Farley on “Saturday Night Live.”

15. Was booted from the speakership after Republicans’ 1998 midterm losses and resigned his seat.

16. Was an early favorite in the 2012 Republican presidential race but was left for dead after his staff quit on him because Callista demanded he go on a Greek cruise in mid-2011.

17. He later revived his campaign to win the South Carolina and Georgia primaries but was lampooned for proposing the U.S. build a moon base by his second term.

18. Has written 28 books, from political manifestos to historical fiction.