The story of the forgotten patriarch who started the Bush family dynasty

The Bush family has been on something of a roll for the past five generations.

If we trace the lineage back to the mid-19th century, we see that the dynasty came to dominate in railroad, finance, and oil industries before seating two of its members in the Oval Office.

The Bushes are potentially looking to accomplish a presidential hat trick with Jeb Bush - son of George H.W. Bush and younger brother of George W. Bush - running for election in 2016.

While the later generations of the Bush family are the most well known, W. and Jeb have their grandfather, Prescott S. Bush, to thank for turning the family name into a dynasty.

We decided to look back at how his influence shaped the Bushes' legacy. This retrospective includes insights from Jacob Weisberg's exhaustive biography, "The Bush Tragedy," and vintage photos.

Born to an Ohio steel and railroad executive and his wife, Prescott S. Bush decided early on that he wanted nothing to do with his father's ventures in manufacturing. He would carve his own success story.

He burst onto the high-society scene as a tall, athletically gifted young man at Yale. He picked up varsity letters in baseball, hockey, and golf, sang with the Whiffenpoof Quartet, and belonged to the school's exclusive secret society, Skull and Bones.

After returning from World War I, Prescott found work selling hardware in St. Louis. There, he met an energetic 18-year-old named Dorothy Walker. Their union marked the beginning of the Walker-Bush lineage.

At the time, Dorothy's father, George Herbert "Bert" Walker, managed the famous Harrison brothers' enterprises at 1 Wall Street. He went on to become president of W.A. Harriman & Co.

Bert pulled some strings and found work for Prescott at the firm, though Prescott refused to admit he had any help getting there. Having the job handed to him betrayed his family's tradition of making a name for yourself.

Still, he used the chance to catapult himself to greater riches and power. He saved the Harrimans from significant losses after the financial crash in 1929 by slashing costs and facilitating a merger with a bank owned by fellow members of Yale's Skull and Bones.

Prescott went on to direct Union Banking Corp., an investment bank that facilitated the transfer of gold, oil, steel, and coal all over the globe during World War II. The bank's assets were later frozen under suspicion that the bank backed Nazi sympathizers.

Fortunately for Prescott, he didn't own his share in UBC; rather, he held it on behalf of a Dutch bank. A degree removed from Hitler's "secret nest egg," he was never found guilty of any crime.

During these years, living in Greenwich, Connecticut, Prescott and Dorothy had five children: four boys and one girl. The Bush kin grew up in a fiercely religious household that encouraged both loyalty and competitiveness. They wanted for nothing, vacationing at the Walker family's summer estate in Kennebunkport, Maine, and attending private schools. Still, Prescott's sense of modesty led him to squash any child's show of privilege.

The couple remained active in local affairs. Prescott moderated town meetings for more than 15 years and Dorothy volunteered at the Red Cross and at a welfare agency.

When Prescott reached his mid-50s, he finished paying off his children's tuition bills and felt financially secure enough to enter politics. In 1952, after a failed run at the US Senate two years prior, Prescott brought along a special guest on the campaign trail to rally supporters: his golf buddy, Dwight Eisenhower, fresh off a landslide presidential election.

Prescott won the Republican seat and served two terms as a Connecticut Senator, between 1952 and 1962. He left a legacy as a Northeastern moderate, supporting civil-rights legislation, larger immigration quotas, and higher taxes, and opposing increasing senators' salary. "In his vision, either an independent income or a monastic lifestyle was required for elected officials," Jacob Weisberg writes in his book.

Prescott retired from the Senate because of ill health. He lived another 10 years, returning to the banking industry, and died of cancer in 1972.

His passion for politics, of course, trickled down to future generations of Bushes. Weisberg writes that, although George H.W. Bush never worked on any of his father's campaigns, he watched closely. He inherited his father's sense of duty.

"Prescott Bush established three essential myths that Bush men lived by," Weisberg writes. "The first is: I made it on my own. The second is: I'm not really rich. The third is: I'm running to serve my country."