Before Ignatius Aloysius O'Shaughnessy became an oil tycoon and philanthropist, a keg of beer started a flow of life-shaping events worth retelling on the cusp of St. Patrick's Day.

Let's start 170 years ago: In the teeth of Ireland's 1840s potato famine, a boot maker named John O'Shaughnessy felt he must sever his family's connection to their longtime isle.

O'Shaughnessys wind back through Counties Clare and Galway to Gaelic times, when they were known as O'Seachnasaigh. In 1543, King Henry VIII knighted a Diarmaid O'Seachnasaigh.

John O'Shaughnessy, the immigrant boot maker, set up shop in Milford, Mass. His son, another boot maker named John, took his new bride, Mary Ann, to Stillwater in 1860. He opened a shop on Main Street and stayed busy after hours. When their 13th child was born in 1885, they had a problem.

"By the time I arrived, mother had run fresh out of all the regular names like John, James and Joseph, and being a good Catholic, she went to the Calendar of Saints. So I became Ignatius."

Ignatius Aloysius O'Shaughnessy — nicknamed Nashe (naysh) — grew up in a home crowded with more than siblings at 703 3rd Av. S. in Stillwater. His father and his friends met regularly and discreetly to determine which struggling neighbors needed aid. Sometimes that meant squeezing in orphans.

As a teenager, Nashe played football, hung from trestles when trains roared overhead and worked as a lumberjack for a St. Croix River mill. Despite the massive flock, his parents made sure their kids were educated.

At 16, Ignatius paid the $100 for tuition, room and board and enrolled at St. John's University near St. Cloud — following brothers Joseph, John, William and James. The little brother helped St. John's fledging football team upset St. Thomas in 1901 at St. Paul' s Lexington Park.

Then the keg was tapped and a train ride decision was made.

The quirks of fate in O'Shaughnessy's early life are chronicled in a new biography, "That Great Heart," written by former St. Paul Pioneer Press editor and longtime St. Thomas spokesman Doug Hennes.

Hennes opens his book in January 1902 when 16-year-old Nashe skips Sunday vespers at St. John's with a couple of buddies — a big no-no. They had hid a beer barrel in the woods and were promptly busted and expelled.

Aboard an eastbound Great Northern train, Nashe had a dilemma: He could change trains at St. Paul's original Union Depot and face his father's head-shaking disappointment down the line in Stillwater. Or he could hop off the train in downtown St. Paul.

He did the latter, shuffling through the cold up the hill to railroad baron James J. Hill's mansion and walking 6 miles down Summit Avenue to St. Thomas along the Mississippi River. Father John Dolphin, the college president, was on his evening stroll.

He'd already heard about the beer-drinking expulsions up at St. John's. One of Nashe's drinking buddies had asked Dolphin if he could be admitted earlier in the day. But the president said "no" after the kid griped about the unfair treatment he'd received.

Dolphin invited O'Shaughnessy in for a warm meal, and the teen told him about the skipped service that got him kicked out of school. The president asked whether he thought the expulsion was warranted.

"Absolutely," Nashe said. "I knew the rule and the penalty. I broke the rule and got caught. They had to fire me."

Impressed with the honesty, Dolphin looked at the kid who'd helped beat his football team a few months earlier — and accepted him on the spot.

After graduating in 1907, Nashe left Minnesota for the insurance and tire-making businesses in Texas, Colorado and Kansas.

He'd married Lillian Smith, a fellow member of St. Mark's Church in St. Paul, and by 1916 they had three kids and were living in Wichita. Oil was discovered just south of the ­Kansas border in Oklahoma.

O'Shaughnessy started buying oil leases and building refineries for his new Globe Oil and Refining business. It wasn't instant wealth. A 3,330-foot well dug in 1920 wound up dry and cost him $50,000.

But by 1930, as the Depression took hold, he had added a refinery in suburban Chicago to his holdings in Oklahoma and Kansas. His philanthropy started in the late 1930s, when he kicked in $400,000 for athletic facilities at St. Thomas — the first of $8.5 million he'd give to his alma mater (worth nearly $100 million when adjusted to 2014 dollars.) His name would soon adorn libraries and auditoriums.

His donations would range from $500 to a North Dakota church in need of a piano to $4.5 million for an ecumenical institute in Jerusalem — after prodding from Pope Paul VI.

"The Lord has been good to me," he once said. "So I figured I might as well spread some of my money around where it will do some good. I came into this world with nothing and figured I'll go out the same way."

On the other side of the O'Shaughnessy ledger, he bought the Cleveland Indians baseball team in the late-1950s, loved skippering his Florida yacht and bought part of an 8,325-acre parcel of Irish lake country, complete with castle, in 1957 when he was 71.

He spent five weeks on his Irish estate in 1958, his first trip to the ancestral home, finding a castle 25 miles north of where his ancestors had lived.

He insisted that the estate's beauty, with 11 islands amid 5,000 lake acres, was his sole reason for his $10,000 stake. A skeptical reporter once asked, "Is there oil under the lakes of Killarney?"

Said O'Shaughnessy: "I told him to be on his way."

Curt Brown's tale on Minnesota's history appears each Sunday. Readers can send him ideas and suggestions at mnhistory@startribune.com