Grier sat on the Supreme Court for nearly a quarter century in tumultuous years. He delivered major opinions in many areas, including bankruptcy law, commerce, patent law, and federal court procedure and jurisdiction. Several of these opinions were important in his day, but few had lasting doctrinal significance. In twentieth-century ratings of Supreme Court justices, Grier is ranked as average. His opinion in the Prize Cases, recognized by Ulysses S. Grant as a "great service" in the nation's "darkest hours," stands as his most important contribution to American constitutional law.

In the meantime, the subject of this notice continued at Dickenson [Dickinson] College. His aptitude for the languages and early instruction had placed him far ahead of all competitors in that branch. He was so thoroughly master of the Latin that he could write it with facility, perhaps as well as his mother tongue; and, though indifferent to, and never troubling himself about, college honors, his superior ability and acquirements were not questioned.

Robert Cooper Grier was born on March 5, 1794 in Cumberland County, Pennsylvania, the eldest of the eleven children of Presbyterian minister Isaac Grier, a member of the Dickinson class of 1788 and his wife Mary Cooper Grier. Schooled by his father, he entered Dickinson at seventeen and finished in one year as a graduate of the class of 1812. Following this, he served briefly as the principal of the Dickinson Grammar School. He then joined his father at his Northumberland Academy, teaching Latin and Greek, and replaced him as headmaster when he died in 1814.