The ‘Today’ Show: A Morning Pioneer Long Before Matt Lauer

NBC’s “Today” show started in 1952 as a bid to lure people away from early morning radio programs.

The brainchild of its creator, Sylvester L. Weaver Jr., it was the first show of its type, pioneering a TV format that other networks came to embrace.

And what started as a two-hour program has grown to become a four-hour live broadcast, an institution that draws millions of viewers each morning as it weaves together news, weather and entertainment.

When “Today” celebrated its 60th anniversary in 2012, President Barack Obama and the first lady, Michelle, offered their congratulations. Mr. Obama said that “over decades and across generations, the ‘Today’ show has become a part of American culture.”

It has been the home for several hosts who became household names, from Barbara Walters to Bryant Gumbel, Katie Couric, Matt Lauer and Al Roker. Mr. Lauer was fired on Wednesday after an allegation of sexual misconduct.

“Today” dominated the morning TV ratings from the end of 1995 to 2012, when it started losing out to its ABC rival, “Good Morning America.”

As ratings sagged in 2012, Ann Curry was ousted as an anchor because she and her co-host Matt Lauer were deemed to lack chemistry. But her removal was deeply damaging for the show. After Ms. Curry said her teary goodbye, the show lost advertising revenue and viewers.

Ms. Curry had felt that the atmosphere behind the scenes at the show had undermined her and she told friends that her final months were a form of professional torture. Mr. Lauer’s indifference to her situation also hurt, she said.

The “Today” show eventually moved past that, however, and viewers returned. Megyn Kelly, the former Fox News anchor, joined this year as a host.

Now, with the firing of Mr. Lauer, NBC News faces a different sort of crisis, one that will likely impact the network for some time.