In 1784, following Britain's recognition of the United States independence, Trumbull returned to London for painting study under West.
His first major work, The Deputation from the Senate Presenting to Cincinnatus the Command of the Roman Armies, was accepted and displayed by the Royal Academy of Arts in that year.
In this work, Trumbull had painted Lucius Quinctius Cincinnatus in the likeness of George Washington.
The painting is now unlocated.
While working in his studio, Trumbull painted Battle of Bunker Hill and Death of General Montgomery in the Attack on Quebec.
Both works are now in the Yale University Art Gallery.

In July 1786, Trumbull went to Paris, where he made portrait sketches of French officers for the Surrender of Lord Cornwallis.
With the assistance of Thomas Jefferson, serving there as the American minister to France, Trumbull began the early composition of the Declaration of Independence.
Over the next 5 years Trumbull painted small portraits of signers, which he would later use to piece together the larger painting.
If the signer was deceased, a previous portrait would be copied, as was the case with Arthur Middleton, whose head position stands out in the painting.
While visiting with each signer or their family, Trumbull, always looking for funding, used the occasion to sell subscriptions to engravings that would be produced from his paintings of the American Revolution.

While in Paris, Trumbull is credited with having introduced Jefferson to the Italian painter Maria Cosway; they became lifelong intimate friends.
Trumbull's painting of Jefferson, commissioned by Cosway, became widely known due to a later engraving of it by Asher Brown Durand, which was reproduced.

Trumbull's Declaration of Independence painting was purchased by the United States Congress, along with his Surrender of General Burgoyne, Surrender of Lord Cornwallis, and General George Washington Resigning His Commission, all related to the Revolution.
 All now hang in rotunda of the United States Capitol.
Congress reportedly authorized only funds sufficient to purchase these four paintings.

Trumbull completed several other paintings related to the Revolution: 
Death of General Warren at the Battle of Bunker's Hill (one version is held by the Boston Museum of Fine Arts);
Death of General Montgomery in the Attack on Quebec;
Capture of the Hessians at Trenton;
Death of General Mercer at the Battle of Princeton;
Washington at Verplanck's Point, a 1790 gift to Martha Washington;
George Washington, commissioned by the City of New York in 1790; and
The Sortie Made by the Garrison of Gibraltar, 1789.
This was once owned by the Boston Athenaeum and  is now held by the Metropolitan Museum of Art in New York City.
In 1784, following Britain's recognition of the United States independence, Trumbull returned to London for painting study under West. His first major work, The Deputation from the Senate Presenting to Cincinnatus the Command of the Roman Armies, was accepted and displayed by the Royal Academy of Arts in that year. In this work, Trumbull had painted Lucius Quinctius Cincinnatus in the likeness of George Washington. The painting is now unlocated. While working in his studio, Trumbull painted Battle of Bunker Hill and Death of General Montgomery in the Attack on Quebec. Both works are now in the Yale University Art Gallery.
In July 1786, Trumbull went to Paris, where he made portrait sketches of French officers for the Surrender of Lord Cornwallis. With the assistance of Thomas Jefferson, serving there as the American minister to France, Trumbull began the early composition of the Declaration of Independence. Over the next 5 years Trumbull painted small portraits of signers, which he would later use to piece together the larger painting. If the signer was deceased, a previous portrait would be copied, as was the case with Arthur Middleton, whose head position stands out in the painting. While visiting with each signer or their family, Trumbull, always looking for funding, used the occasion to sell subscriptions to engravings that would be produced from his paintings of the American Revolution.
While in Paris, Trumbull is credited with having introduced Jefferson to the Italian painter Maria Cosway; they became lifelong intimate friends. Trumbull's painting of Jefferson, commissioned by Cosway, became widely known due to a later engraving of it by Asher Brown Durand, which was reproduced.
Trumbull's Declaration of Independence painting was purchased by the United States Congress, along with his Surrender of General Burgoyne, Surrender of Lord Cornwallis, and General George Washington Resigning His Commission, all related to the Revolution.  All now hang in rotunda of the United States Capitol. Congress reportedly authorized only funds sufficient to purchase these four paintings.
Trumbull completed several other paintings related to the Revolution: 
Death of General Warren at the Battle of Bunker's Hill (one version is held by the Boston Museum of Fine Arts);
Death of General Montgomery in the Attack on Quebec;
Capture of the Hessians at Trenton;
Death of General Mercer at the Battle of Princeton;
Washington at Verplanck's Point, a 1790 gift to Martha Washington;
George Washington, commissioned by the City of New York in 1790; and
The Sortie Made by the Garrison of Gibraltar, 1789. This was once owned by the Boston Athenaeum and  is now held by the Metropolitan Museum of Art in New York City.
John Trumbull