The stocky, bespectacled Bowen was speaker of the Indiana House and was very popular when he ran for governor and won in a landslide, defeating former Democratic Gov. Matthew Welsh.
Former Sen. Dick Lugar said Sunday that Bowen "was the best example of public leader in our state and nation because of his demeanor, intellect, wisdom and range of abilities."
"Whether it was a call from a patient, a constituent, or his country, Doc could not refuse to serve," Lugar said in a statement.
As governor, Bowen made state-backed property tax relief his top campaign pledge as those taxes had more than doubled in the previous decade. Legislation passed the next year doubled the sales tax to 4 percent and dedicating the extra revenue to property tax cuts. The proposal was so hotly contested that it only passed the state Senate when Bowen's lieutenant governor, Robert D. Orr, cast a tiebreaking vote.
However, the public largely embraced the tax system changes, boosting Bowen's popularity.
Under an amendment to the state constitution, he was the first governor since the mid-1800s eligible to seek a second consecutive term, which he easily won in 1976.
In 1979, Bowen refused to extradite Indiana University basketball coach Bob Knight to Puerto Rico after the coach was convicted in absentia and sentenced to six months in jail for hitting a policeman during the Pan Am Games.
Bowen was born Feb. 26, 1918, near the northern Indiana town of Rochester. He received bachelor's and medical degrees from Indiana University and joined the Army Medical Corps after completing his internship in 1943. His World War II service included going ashore with the first waves of Allied troops during the invasion of Okinawa in 1945.
Following the war, Bowen started a family medical practice in Bremen, a small town about 20 miles south of South Bend, which he continued for 25 years.
Bowen once said his medical career, during which he estimated he delivered 3,000 babies, taught him "how to approach emergencies and problems with a certain amount of calmness and common sense."
After leaving the governor's office, Bowen taught at Indiana University until Reagan appointed him HHS secretary. He held the post until Reagan left office in January 1989.
On Sunday, Bowen's alma mater lauded his accomplishments and noted that last year, the university's School of Public Health awarded him its Ryan White Distinguished Leadership Award, which is named for an Indiana teenager who became an early face of the AIDS epidemic.
"He was an extraordinarily impressive man who leaves behind a legacy of immense accomplishment that will be felt across Indiana and the nation for decades to come," IU President Michael McRobbie said.
Bowen said that his greatest accomplishment as health secretary was persuading Reagan to back a bill providing insurance for catastrophic illnesses that passed Congress in 1988 in the first major expansion of Medicare since it was established in 1965. But the bill was repealed by Congress the next year, following complaints from retirees who already had coverage and from higher-income people who had to pay a surtax to finance two-thirds of the program.
Bowen had four children with his first wife, Beth, who died of cancer in 1981 just days before her husband's second gubernatorial term ended. His son, Robert, tried to extend the Bowen family election success, but lost to another second-generation politician, Evan Bayh, in the 1986 race for Indiana secretary of state. Bayh was later elected governor.
Bowen married Rose Hochstetler, a widow from Bremen, in 1981. They moved back to Bremen in 1989 after his time in Washington, but she died of cancer two years later.
Bowen was married in 1993 to Carol Mikesell, who had been a patient of his some 30 years earlier, during which time he delivered her two children.