Viacom’s Upheaval Continues With the Exit of Music and Entertainment Group President Doug Herzog

He first joined the company in 1984

Viacom finally has a new CEO and isn't merging with CBS after all, but that hasn't put a stop to the company's 2016 upheaval.

Doug Herzog, president of Viacom's Music and Entertainment Group, announced today that he'll be leaving the company next month. He oversees MTV, Comedy Central, VH1, Spike and Logo.

In a memo sent to staff, Herzog said he'll be leaving Viacom as of Jan. 12. "It was a helluva run, and I would wish it on anyone. I loved every minute of it," he said.

Just last week, Viacom's parent company, National Amusements, which owns 80 percent of the voting shares of both Viacom and CBS, decided to pull the plug on discussions of a potential merger.

That same day, the company announced that Bob Bakish, who had been serving as acting president and CEO since Nov. 15, has been named permanent CEO in light of the CBS-Viacom decision.

While Herzog's departure comes just a week after Bakish was named permanent CEO, Herzog praised Bakish in his staff memo.

"Reinventing the brands and innovating with content are the great core strengths of this company. Bob is already bringing true leadership and vision to Viacom. He is a big believer in the power of these brands across all platforms. I promise you are in very good hands with him, as well as your tremendous brand leaders," he said.

Herzog's exit shakes up a company that just seemed to reclaim some stability last week after the CBS merger was called off. 

In a letter sent to both boards from National Amusements CEO Sumner Redstone and his daughter Shari, who is vice chair, the two stated that, "Following the management changes that the Viacom Board put in place, we have been very impressed with the forward-looking thinking and strategic plan being pursued under Bob Bakish's leadership."

That seemed to put an end to a year of upheaval, highlighted by a battle between Redstone and former Viacom president and CEO Philippe Dauman over the future of the company.

The parties finally settled their differences in August, and Dauman agreed to depart as president and CEO of Viacom.

Herzog first joined MTV in 1984, and became president of MTV Productions, before moving to Comedy Central in 1995. He left the company for gigs as president of Fox and USA before returning to Viacom in 2004, serving as president of the entertainment division.

Herzog has installed new presidents at the heads of almost all his networks in the past two years. In October, he tapped Chris McCarthy, who already serves as president VH1 and Logo, to head up MTV as well, replacing Sean Atkins. In May, Comedy Central president Michele Ganeless exited; she was replaced by president of original programming Kent Alterman.

While Viacom has reversed years of ad revenue decline in recent months—according to new data from Standard Media Index, the company's ad revenue was up year-over-year in October and November—some of its channels still need CPR. Comedy Central's November ad revenue was down 11.7 percent year-over-year, according to SMI.

During last month's earnings call, Bakish had noted that turning around Comedy Central and MTV—two networks overseen by Herzog—were among his top priorities as CEO.