The Post’s Chris Cillizza breaks down former House speaker Dennis Hastert's indictment on charges that he broke bank laws by withdrawing large sums of money and lying about it to federal authorities. (Nicki DeMarco/The Washington Post)

Former House speaker J. Dennis Hastert, who was indicted Thursday on charges of concealing bank withdrawals related to a secret $1.7 million payoff, made a fortune through real estate investments before leaving Congress.

In one controversial trans­action conducted through a trust, Hastert reaped millions of dollars by selling farmland near the site of a proposed highway that was to be financed in part with funds that the then-speaker had earmarked.

The rise in Hastert’s personal wealth during his time in Congress was a marked change in lifestyle for the former high school teacher and wrestling coach.

When he arrived in Washington in 1987, Hastert’s biggest asset was a 104-acre farm in southern Illinois that his wife inherited, worth between $50,000 and $100,000, according to his personal financial disclosure. By the time the Illinois Republican left 20 years later, his reported assets had swelled to between $3.1 million and $11.3 million, largely because of his investments in farmland in booming parts of Illinois.

Hastert then embarked on a lucrative career as a lobbyist, getting tapped last year to lead the government relations practice at the firm Dickstein Shapiro. His clients there included Peabody Energy, the Secure ID Coalition, Lorillard Tobacco and Fuels America, according to lobbying records. He resigned from the firm Thursday.

It was not until after he was elected speaker in 1999 that Has­tert began stepping up his land investments, parlaying some early real estate deals and a small inheritance he had from his father.

By the mid-2000s, Hastert and two partners had amassed 138 acres of farmland outside Plano, Ill., several miles from the proposed site of the Prairie Parkway, a highway connector that would have cut through the northern Illinois countryside.

The then-House speaker’s ownership of the property was not a public record, as it was held under a blind land trust called the Little Rock Trust No. 225, which identified only one partner in public filings: Dallas Ingemunson, a local GOP leader and longtime political mentor to Hastert.

At the time, Hastert was championing the highway, which opponents said would tear up the farming region and hasten its suburbanization.

“Our sense was this was being crammed down the throats of a rural community backed by commercial interests, and we called him the chief cheerleader of the project,” said Jan Strasma of the Citizens Against the Sprawlway, a local group against the construction of the Prairie Parkway. “He had the power and could put so much money behind the project, it was hard to oppose.”

Hastert eventually earmarked $207 million for the $1 billion parkway project in a federal transportation bill, which then-President George W. Bush signed during a trip to Hastert’s district in August 2005.

“The Prairie Parkway is crucial for economic development in Kendall and Kane counties,” Bush said during the signing, held at a Caterpillar plant before thousands.

Four months after the bill was signed, Hastert’s trust sold the land to a real estate developer who planned to build 1,700 homes on the parcel. Hastert’s share of the proceeds was worth more than $3 million, Ingemunson later told the Chicago Tribune.

But his role in the deal was not made public until Hastert reported real estate transactions in the area on his annual personal financial disclosure in May 2006, which the Sunlight Foundation used to match against local land records and connect him to the trust.

Hastert dismissed the idea that the land was more valuable because of his earmark. “Nothing to it,” Hastert said at the time.

In the end, the Prairie Parkway never came about. Strasma’s group filed a lawsuit challenging the environmental impact statement, and the federal government rescinded the approval for the project after it failed to get local funding priority. In 2012, the money was diverted to widen an existing two-lane highway in the same area.

Hastert continued to invest in land after the Plano sale, taking as payment from that deal — along with some cash — another parcel in booming Kendall County. He estimated that property’s worth at between $1 million and $5 million when he left office in 2007.

Paul Kane contributed to this report.