Waithe also made history when she became the first black woman to win an Emmy for comedy writing.
The "Seinfeld" actress is now tied with Cloris Leachman's record eight Emmys wins by a singular performer. Louis-Dreyfus submitted the season six finale, "Groundbreaking", for Emmy consideration this year. She is also tied to Cloris Leachman for having the most individual Primetime Emmy Awards of any performer.
The glitzy ceremony in downtown Los Angeles - the first under the administration of President Donald Trump - was expected to have a distinctly political flavour, with host Stephen Colbert likely not to pull his punches.
"I remember the first time we won this award", creator Lorne Michaels said in accepting the show's trophy for best variety sketch series. The series has been an awards-season juggernaut for the last few years, kicking Modern Family off its Emmys pedestal in the best-comedy category after a long streak.
The 69th prime time Emmy Awards was a record-breaking night for TV veterans and newcomers in multiple categories.
The actress also thanked HBO and all of the show's writers, directors, producers and her costars, whom she loves "dearly" and relies on dearly.
"It's nuts", Louis-Dreyfus said, summing up her remarkable run.
"We did have a whole storyline about an impeachment but we abandoned that because we were anxious someone else might get to it first", Dreyfus said.
Now-legendary Louis-Dreyfus accepted her award toward the end of the evening, and kept her speech to the packed house at Los Angeles' Microsoft Theater short but still meaningful.
Congratulations to each and every one of our talented and accomplished Northwestern graduates in the creative arts and entertainment industry, many of whom are working on and for Emmy-winning and nominated programming.
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