Even history buffs might be pressed to identify all 10 events in this History Channel series. But each of the 10 days triggered significant changes in American life.

"We didn't want to burden the series with the 10 most important events," said filmmaker Joe Berlinger, co-executive producer of the series. "We wanted days that offered interesting storytelling or days where the outcome was unexpected."

About a dozen historians were asked to brainstorm about which events they thought would qualify, said Susan Werbe, vice president of programming for the History Channel and series executive producer.

The historians avoided obvious events such as the bombing of Pearl Harbor and warned against too-recent events, such as the Sept. 11 attacks, because not enough time had passed for historical perspective, she said.

Ten independent filmmakers were matched with 10 events, Berlinger said, "and each produced a very different documentary that could stand on its own." The films include a variety of techniques such as re-enactments, interviews, archival footage and animation.