M. Peter Miller Jr. and his wife, Ruth, read a copy of The Washington Times-Herald in 1949. (Photo by Wide World Photo)

Ruth Tankersley, a scion of the McCormick media dynasty who served a tumultuous 19 months as a newspaper publisher in Washington and for more than six decades was a celebrated breeder of Arabian horses, died Feb. 5 at her home in Tucson. She was 91.

A daughter, biographer Kristie Miller, confirmed the death and said her mother had Parkinson’s disease.

In addition to her connection to the Chicago Tribune publishing empire, Mrs. Tankersley, known as “Bazy,” descended from a formidable political family, as well.

Her parents and stepfather served in Congress. So did her maternal grandfather, Mark Hanna, a Republican political kingmaker who had been an adviser to President William McKinley and a force in the building of the Panama Canal.

Bazy McCormick Miller, as she was known in the 1940s after marrying for the first time, was prepared by her uncle, Robert R. McCormick, to be heir apparent to the Tribune company. The Tribune was one of the world’s most powerful newspapers, a champion of an isolationist foreign policy and an influential voice in the Republican Party.

Ruth Tankersley with Al-Marah ala Shan, an Arabian colt that she donated to auction off at the Arabian Nights Bazaar in Washington in 1951. (Washington Post file photo )

Robert McCormick, a bombastic and mercurial publisher, was childless and doted on his niece. She got early training running a daily newspaper with her first husband in La Salle, Ill., and organizing “Twenties for Taft” clubs to support 1948 GOP presidential candidate Robert A. Taft. In 1949, her uncle tapped her to run the Tribune’s newly purchased Washington Times-Herald. She was 28.

The Times-Herald, the Tribune’s chief presence in the nation’s capital, was known for its sensationalistic coverage of politics. Its circulation of 278,000 made it one of the city’s biggest newspapers, a major competitor with the Washington Star, The Washington Post and the Washington Daily News.

Robert McCormick bought the tabloid, he said, to bring “the American point of view” to Washington.

In a nod to her uncle’s well-known political and geographic sympathies, Bazy Miller described herself a daughter of the Midwest, a region that was “the heart and soul and stability of the country.” Washington, she added, was in contrast “a parasite community.”

Following dictates from Chicago, the paper was a mouthpiece for right-wing causes and played a role in unseating Sen. Millard E. Tydings (D-Md.) in 1950 in favor of a Republican candidate, John Marshall Butler.

The Times-Herald published a four-page section during the race that included a composite photograph showing Tydings apparently casting an admiring gaze at Communist Party leader Earl Browder.

The composite — two separate images pasted together — was one of many factors that provoked a Senate subcommittee investigation of the tactics used in the Tydings race. In testimony, Bazy Miller said her friend Sen. Joseph R. McCarthy (R-Wis.), the reckless anti-Communist crusader, asked her to print the special section.

A second scandal befell the paper in 1951, when Drew Pearson filed a $5.1 million suit against the Times-Herald, McCarthy and others for what he said was a conspiracy to smear his reputation. The columnist, a frequent McCarthy critic, dropped the suit in 1956 after reaching an undisclosed settlement.

Bazy Miller’s newspaper career was abbreviated. In April 1951, she was recalled to Chicago and feuded bitterly with her uncle, who was sometimes called “the colonel.” She said she was tired of his meddling.

“I understood when I went to the Times-Herald I was to have full control,” she said at the time. “That control was not given me. . . . There is some difference in our political beliefs. I have broader Republican views than he has. I am for the same people as the colonel, but I am for some more people.”

Another factor was her divorce from her first husband, M. Peter Miller Jr., in 1951 to marry a Times-Herald editor, Garvin “Tank” Tankersley. She said her uncle disapproved of the nuptials, ostensibly because of Tankersley’s lower social status, and that McCormick told her to choose between Tankersley and the Tribune Co.

Bazy Tankersley resigned from the Times-Herald, which she later scrambled unsuccessfully to buy before its sale to The Washington Post in 1954.

The Tankersleys began a long career as horse breeders at their farm and estate in Montgomery County, called Al-Marah, based on an Arabic word for “oasis.” Their property, initially in Bethesda and later in Barnesville, was a lively gathering place for soirees and Republican fundraisers.

(Mrs. Tankersley’s political allegiances shifted slowly over the decades and, in 2008, she voted for Democratic presidential nominee Barack Obama, her daughter said.)

Over time, the Tankersleys’ horse-breeding and horse shows became the focal point of their public lives. Their business, which relocated to Tucson in the mid-1970s, became one of the largest private horse farms of its kind in the world.

Dianne De Franceaux Grod, a veteran rider and trainer who once worked for Mrs. Tankersley, said her former boss “founded a line of breeding she favored that ended up being one of the most versatile group of horses in the Arabian world. They won in reining, dressage, hunters, jumpers, sport horse and endurance, including the Tevis Cup, the most coveted endurance award.”

In 2001, Mrs. Tankersley bequeathed her property to the University of Arizona to continue using it as a working ranch.

“You see, I come from that old-fashioned background of noblesse oblige: If you’re born with money, you have an obligation to do good works for others,” she said in a 1998 biography titled “. . . And Ride Away Singing.” “Only in recent years did I come to feel that through Arabian horses I might do more for my fellows than in any other way.”

Ruth Elizabeth McCormick was born in Chicago on March 7, 1921, to J. Medill McCormick and the former Ruth Hanna. Her childhood nickname became Bazy — a mispronunciation of Baby — because her mother was also Ruth.

She was 4 when her father committed suicide, and she spent parts of her childhood in New Mexico with her mother and stepfather, Albuquerque lawyer and banker Albert Gallatin Simms.

Bazy, whose mother owned and operated a dairy and breeding farm near Byron, Ill., began raising Arabian horses as a teenager. She studied genetics at Bennington College in Vermont and later helped start two private schools in the Washington area — the Primary Day School in Bethesda and the Barnesville School — and another one in Tucson.

Garvin Tankersley died in 1997. A daughter from that marriage, Tiffany Tankersley, died in September.

Survivors include two children from her first marriage, Mark Miller of Orlando and Kristie Miller of Washington; two stepchildren, Anne Sturm of Barnesville and Garvin Tankersley Jr. of Frederick; six grandchildren; and two great-granddaughters.

Her son, Mark, started the Arabian Nights, a dinner theater equestrian show in Kissimmee, Fla.