The decision by Rep. Nancy Pelosi (D-Calif.) to leave Congress after almost four decades marks the end of an era for both the powerhouse Democrat and her party at large.

Nancy Pelosi announced on Thursday that she would not seek re-election to the US House of Representatives, bringing to a close one of Washington’s most extraordinary political careers.

"We have made history, we have made progress," Pelosi said in her message.

Representative Nancy Pelosi announced her retirement from Congress after serving for decades. More Videos. Trump suggests shutdown to blame for Republican election losses

Nancy Pelosi is bringing her history-making career in the U.S. House to an end, but she leaves a linguistic legacy in Congress and beyond.

Her legacy as speaker includes her strong opposition to the Iraq War during President George W. Bush’s tenure and her pivotal role in passing landmark legislation under President Barack Obama.