Whatever President Obama had planned for life after the presidency, the election of Donald Trump will likely change those plans.

Instead of building on his legacy, he'll be defending it. Instead of helping to nurture his Democratic Party as an elder statesman, he'll be helping to rebuild it — finding new generational leaders who can carry the banner in future elections.

And instead of providing friendly counsel to President Hillary Clinton, he'll have a more complicated relationship with President Donald Trump.

"Obama's post-presidency just got exponentially more interesting," said Cody Foster, a University of Kentucky historian who has studied the post-presidential lives of former presidents.