Captain America: Civil War is schedule for release on May 06, 2016. Apparently the civil war aspect describes a split in the Avengers between those (led by Captain America) who want to remain autonomous and those (led by Iron Man) who want government oversight.
Watch full screen. This is the second trailer - the first is below.
Marvel's synopsis of the plot:
Marvel’s “Captain America: Civil War” finds Steve Rogers leading the newly formed team of Avengers in their continued efforts to safeguard humanity. But after another incident involving the Avengers results in collateral damage, political pressure mounts to install a system of accountability, headed by a governing body to oversee and direct the team. The new status quo fractures the Avengers, resulting in two camps—one led by Steve Rogers and his desire for the Avengers to remain free to defend humanity without government interference, and the other following Tony Stark’s surprising decision to support government oversight and accountability.Here's the first trailer: