James Comey
James Comey was the FBI Director, he was fired in May. He was only the second FBI Director to be fired. Comey was handling the Russia probe into the 2016 elections. He was blamed for causing controversy for the Trump Administration.
Walter M. Shaub Jr.
Walter Shaub was the Director of the Office of Government Ethics. He resigned because of the Finances of Trump, which caused conflict between him and the White House. When Shaub resigned, he called the Trump Administration a laughing stock.
Michael Dubke
Michael Dubke was the White House Communications Director. He resigned in May and was replaced by Scaramucci.
Sean Spicer
Sean Spicer was the White House Press Secretary. He resigned in July after months of battling the press and losing. August will see Spicer leaving the White House. He disagreed with having Anthony Scaramucci as the new White House Communications Director.
Reince Preibus
Reince Preibus was the White House Chief of Staff. He served in that position for 6 months before he resigned. He had a public feud with Anthony Scaramucci and was replaced by General John Kelly.
Anthony Scaramucci
Anthony Scaramucci was the White House Communications Director for 10 days. He spoke badly about the Trump administration. John Kelly was instrumental in his removal.
This is the list so far and based on how Trump is operating, more persons could soon be hired and fired. Every day, any day we have to expect some new drama.