During the Revolutionary War, the British and Americans conducted a frenetic shipbuilding race through the spring and summer of 1776, at opposite ends of the lake, and fought a significant naval engagement on October 11 at the Battle of Valcour Island.

[21] The necessity of controlling the two forts at Ticonderoga and Crown Point placed Lake Champlain as a strategic arena during the Revolutionary War.

[22] Ethan Allen, accompanied by 200 Green Mountain Boys, was ordered to capture Fort Ticonderoga and retrieve supplies for the fight in Boston.

Benedict Arnold shared the command with Allen, and, in early May 1775, they captured Fort Ticonderoga, Crown Point and the southern Loyalist settlement of Skenesborough.

[24] Despite the strategic advantage of controlling a direct route to Quebec by way of the Champlain Valley, the American siege of British Canada during the winter of 1775 failed.

This was not the case, and the rebel army struggled to take Quebec with diminishing supplies, support, and harsh northern winter weather.

[25] The Continental Army was forced to camp outside Quebec's walls for the winter, with reinforcements from New York, Pennsylvania, Massachusetts, New Hampshire and Connecticut allowing the soldiers to maintain their siege of the city.

[26] The reinforcements traveled hundreds of miles up the frozen Lake Champlain and St. Lawrence River, but were too late and too few to influence a successful siege of Quebec.

[26] By the October 1776, the Continental Army had 16 operating naval vessels on Lake Champlain: a great increase to the four small ships they had at the beginning of the summer.

[22] General Benedict Arnold commanded the American naval fleet on Lake Champlain, which was composed of volunteers and soldiers drafted from the Northern Army.

Upon ceasefire, Arnold called a council of war with his fellow officers, proposing to escape the British fleet via rowboats under the cover of night.

[28] With no hope of fighting off the powerful British navy, Arnold ordered his men to run their five vessels aground in Ferris Bay, Panton, Vermont.

The depleted Continental army escaped on land back to Fort Ticonderoga and Mount Independence; however, they no longer controlled the Lake Champlain waterway.

As the British abandoned Crown Point and returned to Canada for the winter, the Americans reduced their garrisons in the Champlain Valley from 13,000 to 2,500 soldiers.

On October 7, 1777, American General Horatio Gates, who occupied Bemis Heights, met Burgoyne's army at the Second Battle of Freeman's Farm.

Similar to the experience of Salmon Dutton, former colonial militia Major General Hezekiah Barnes settled in Charlotte, Vermont, in 1787.

It was fought just prior to the signing of the Treaty of Ghent, and the American victory denied the British any leverage to demand exclusive control over the Great Lakes or territorial gains against the New England states.

Following the War of 1812, the U.S. Army began construction on "Fort Blunder": an unnamed fortification built at the northernmost end of Lake Champlain to protect against attacks from British Canada.

Its nickname came from a surveying error: the initial phase of construction on the fort turned out to be taking place on a point 3⁄4 mi (1.2 km) north of the Canada–U.S.

This status enabled its neighboring states to apply for additional federal research and education funds allocated to these national resources.

[40] In 1609, Samuel de Champlain wrote that he saw a lake monster 5 ft (1.5 m) long, as thick as a man's thigh, with silver-gray scales a dagger could not penetrate.

[42] A Vermont Historical Society publication recounts the story and offers possible explanations for accounts of the so-called monster: "floating logs, schools of large sturgeon diving in a row, or flocks of blackbirds flying close to the water".

[43] In 2022, it was reported that a feature dramatic film, Lucy and the Lake Monster, was in the works about a young orphan girl and her grandfather looking for Champ.

[44][45][46][47][48] A pollution prevention, control and restoration plan for Lake Champlain[49] was first endorsed in October 1996 by the governors of New York and Vermont and the regional administrators of the United States Environmental Protection Agency (EPA).

Renowned as a model for interstate and international cooperation, its primary goals are to reduce phosphorus inputs to Lake Champlain, reduce toxic contamination, minimize the risks to humans from water-related health hazards and control the introduction, spread, and impact of non-native nuisance species to preserve the integrity of the Lake Champlain ecosystem.

[50][51] Agricultural and urban runoff from the watershed or drainage basin is the primary source of excess phosphorus, which exacerbates algae blooms in Lake Champlain.

The most problematic blooms have been cyanobacteria, commonly called blue-green algae, in the northeastern part of the lake: primarily Missisquoi Bay.

The lake is also part of the 740-mile (1,190 km) Northern Forest Canoe Trail, which begins in Old Forge, New York, and ends in Fort Kent, Maine.

At 226 acres (91 ha), Grand Isle State Park contains camping facilities, a sand volleyball court, a nature walk trail, a horseshoe pit and a play area.

Button Bay State Park in Ferrisburgh features campsites, picnic areas, a nature center and a swimming pool.