Somerville's Executors v. Hamilton was a case heard by the United States Supreme Court in 1819. The dispute centered around an agreement between two parties, Somerville and Hamilton, that involved the transfer of land from one to another. Somerville had agreed to sell his property to Hamilton for a certain sum of money; however, before he could do so he died without making any formal conveyance or deed transferring ownership rights over the land. After his death, Somerville's executors sought to recover payment from Hamilton on behalf of their deceased client while also attempting to retain title over the property in question. In its ruling, the court held that although there was no written contract between both parties at hand and thus no legal obligation for either party under common law principles alone; nevertheless it found that equity should prevail in this situation as there had been sufficient evidence presented showing mutual assent between both sides regarding their agreement concerning said land sale transaction which would be binding upon them despite not being formally documented or executed prior to Somervilles' death.

In Somerville's Executors v. Hamilton, the Supreme Court was tasked with determining whether a state court had jurisdiction over an action brought by executors of a will in Virginia against defendants who resided in Maryland. The majority opinion held that the state court did not have jurisdiction because it lacked authority to extend its power beyond its own borders and into another sovereign state. Justice Story dissented from this ruling, arguing that there were no constitutional impediments preventing states from exercising their judicial powers across jurisdictional boundaries when necessary for justice to be served. He argued that such an exercise of power would not violate any principles of comity between states or interfere with federal laws; rather, he contended it was essential for courts to be able to adjudicate disputes involving parties residing in different jurisdictions if they are related through common questions of law and fact. Furthermore, he noted that allowing one party access only to his home-state courts could lead to unfairness as well as unequal protection under the law since some litigants may lack sufficient resources or connections within their home-state’s judiciary system which could result in them being denied justice altogether due solely on account of where they reside.