Junius was the son of William Ward and his wife Sarah Johnson Ward. Sarah was the daughter of Colonel Robert Johnson of Scott County, and the sister of Richard M. Johnson, Vice President of the United States under Martin Van Buren, 1837-1941.

Junius was one of the first planters in the Mississippi Delta. In October of 1820, just three years after Mississippi became a state, the United States and the Choctaw Nation signed the Treaty of Doak's Stand, whereby the Choctaws ceded a vast portion of their lands in Mississippi to the United States government in exchange for lands in Arkansas. The Choctaw ceded their remaining lands under the Treaty of Dancing Rabbit Creek, signed in 1830. Junius' father William accepted a position as Choctaw Nation Indian Agent, and served in this position from 1821 until 1833. Ward lived in Mississippi during the time he was agent. His agency was located on the Natchez trace in present-day Madison County.

After the land opened up after the Treaty of Doak's Stand in 1820, pioneers and planters began moving into the Mississippi Delta to settle and establish plantations. Those that moved to the Delta generally came from either Kentucky or South Carolina. Those from Kentucky were for the most part related to each other or at the very least friends. The Wards and the Johnsons were two of these families.

Junius was one of the first, if not the first planter to reach Washington County. One account states he reached Washington County from Scott County, Kentucky, in 1822. Other accounts place his arrival anywhere between 1825 and 1828. The land patents for land in Washington County are dated 1831, though other records show he actually purchased the land much earlier, in 1826. No matter when he arrived, or when he purchased his first land, it is indisputable that Junius went on to acquire a considerable amount of rich bottom land in Washington County. Junius amassed a sizeable fortune from his cotton interests.

Junius married Matilda Viley on August 28, 1824, in Scott County, Kentucky. Matilda was the daughter of pioneer thoroughbred breeder, George Viley, and his wife Martha Ann Janes Viley, of Scott County, Kentucky.

In 1829, Junius built the "Erwin House," overlooking Lake Washington. The house still stands, and is the oldest extant structure in Washington County.

In 1853, Junius, his brother-in-law Capt. Willa Viley, General Abe Buford, and Richard Ten Broeck, jointly purchased the famed thoroughbred racehorse Lexington for $2,500. Lexington was a bay colt bred by Dr. Elisha Warfield at Warfield's stud farm, The Meadows, near Lexington, Kentucky. Lexington was known as the best race horse of his day, winning six of his seven races. He was retired in 1855 due to poor eye sight. Junius and his partners sold Lexington in 1858 for $15,000, reportedly the then-highest price ever paid for an American horse. Lexington went on to become the most successful sire during the second half of the nineteenth century. He was the leading sire in North American sixteen times, from 1861 through 1874, and then again in 1876 and 1878. He was the sire of Cincinnati, Ulysses S. Grant's favorite horse. Lexington was part of the first group of horses inducted into the Racing Hall of Fame in 1955. The Belmont Lexington Stakes runs every year at Belmont Park in honor of Lexington, as does the Lexington Stakes at Keeneland Race Course. Lexington served as the model for the top of the Woodlawn Vase, given to the winner of the Preakness Stakes at Pimlico

Although they resided in Missisippi, Junius and Matilda never lost their Kentucky ties. Junius commissioned the construction of a home, now known as Ward Hall, the grandest Greek Revival house in Kentucky, and in many opinions, one of the finest examples of a mid-19th century classical building in the United States. It is said that Junius paid $50,000 in gold for construction of the grand mansion, which was completed in the late 1850s. The imposing mansion sits atop a hillside on the Frankfort Road a mile west of Georgetown, Kentucky. When built, the mansion overlooked a 500-acre estate. The massive 12,000-foot mansion measures nearly seventy-five feet square and forty feet high, and boasts twenty-seven foot high Corinthian fluted columns, a nautilus-chambered double elliptical staircase, fourteen-foot ceilings, and a central hallway, sixty-five feet long and fourteen feet wide. Hand carved walnut woodwork, imported marble mantels and Sheffield silver adorn the home.

The War Between the States decimated Junius's fortunes. He had to pay over a good deal of money on notes he had cosigned, and his cotton operation was destroyed. Junius was forced to relinquish his Scott County estate, as well as two properties in Newport, Kentucky, in 1867, in order to satisfy his debts. He also underwent bankruptcy proceedings in Mississippi.

Ward Hall still stands.

Junius and Matilda were the parents of nine children:
William E. Ward, 1830 - b/w 1848/9 and 1857
George Viley Ward, 1832 - 1921
Elizabeth "Betty" Ward, 1834 -
Sarah "Sallie" Ward, 1836- 1857
Martha Ward, 1837 - 1839
Mary Ward, 1839 - 1852
Junius R. Ward, Jr., 1843 -
Robert J. Ward, 1846 - 1850
Matilda "Mattie" Ward, 1850 - 1940

Seven of these children - all but Betty and Mattie- are buried in the Ward Lot at Lexington Cemetery.

Junius purchased the lot in August of 1857. Five of Junius and Matilda's kids were buried/re-interred on December 2, 1857: Robert, Martha, Mary, Sally, William.

Junius, wife Matilda, and daughter-in-law Maria Williams Ward were reinterred at Lexington, from Greenville, Mississippi, on December 7, 1905.

Son Junius Jr. was buried at Lexington on November 5, 1917; and son George Viley Ward was buried at death on January 17, 1923.

A bible record lists Junius's death as August 26, 1883; his obituary gives a death date of August 4, 1883.