Wednesday night was a big one for Bill Hennessy.

More than 100 people jammed O’Fallon’s city council chambers to watch as Hennessy took his first oath as mayor.

Hennessy, 51, had taken the oath five times before over a decade as a city councilman.

He promised to improve communication at city hall to make O’Fallon “a place we can all be proud of again.”

He pledged better government by keeping the business community informed and by preventing politics from interfering with city’s core functions.

“I cannot guarantee instant change or promises to alleve all of our problems overnight, but I can assure you we will be better,” he said Wednesday night. “O’Fallon is too great of a city to let it fall into the hands of personal agendas.”

Also taking the oath tonight were re-elected councilmen Bill Gardner, Rick Lucas, as well as former Councilman John Haman Jr. and first-term Councilman Bob Howell.

All were sworn in by City Clerk Pam Clement.

The city has weathered bitter infighting recently over the departure of its police chief and an investigation of the city administrator, which together cost taxpayers upward of $100,000.

Hennessy replaces one-term Mayor Donna Morrow, who decided not to run for a second term in this month’s election.