A 10-day stretch in 2015 was marked with historic events and powerful speeches. It came to define the presidency of Barack Obama.

That time period was marked achievements and heartbreaks, according to Obama's speechwriter Cody Keenan, who detailed the whirlwind 10 days in his book "Grace."

Obama tackled the Obergefell decision, which legalized same-sex marriage, the Affordable Care Act decision, the Charlestown church shooting and more in June of 2015.

Obama heavily edited Keenan's draft speech for the Charlestown church shooting in which nine people were killed. He crossed out full pages, Keenan said on Greater Boston.

"He's a good boss... He brought me in, talked to me for about a half hour and made me feel better about it," Keenan said of Obama.

"He was always our chief speechwriter, not me. He could always take one of our drafts to a higher place," Keenan said.

Watch: Obama speechwriter shares the 10 days he thinks defined that presidency