Before becoming primary rivals, Gingrich and Perry spent years as allies.
In 2010, Gingrich wrote a glowing foreword to Perry's last book, "Fed Up! Our Fight to Save America From Washington."
That year, the pair appeared together at a book signing at a Barnes & Noble in southwest Fort Worth. At the signing, Gingrich praised Perry's leadership and suggested President Obama seek out Perry for advice.
"I have to say there are very few people who I think could do a better job leading the country than Gov. Perry," Gingrich said.
More recently, Gingrich and Perry have occasionally attacked one another, though often with less attention than they have given to other contenders such as Mitt Romney.
In September, Gingrich was asked if his writing the forward to Perry's 2010 book amounted to an early endorsement. Gingrich replied it didn’t, but said: "If he wants to write another book, I'll write another forward."
Later that month, Perry said his perfect running mate would be some combination of Herman Cain and Gingrich.
Perry's tone shifted later in the year once Gingrich surged to near the front of many polls. Perry and a Perry-supporting super PAC started pointing out Gingrich’s political liabilities. In early December, Perry called Gingrich’s multiple marriages “an important issue” in the race. The campaign also accused Gingrich of flip-flopping on the issue of government-mandated healthcare.
Yet as of noon today, Make Us Great Again, the Super PAC that spent millions backing Perry's presidential bid but was not allowed to coordinate with the campaign, had not taken down this video criticizing Gingrich and Romney.
In his speech today ending his campaign, Perry appeared ready to look past Gingrich's foibles.
"And Newt is not perfect, but who among us is?" Perry asked. "The fact is, there is forgiveness for those who seek God and I believe in the power of redemption, for it is a central tenet of my Christian faith."