On May 28, 1830, the United States Congress passed the Indian Removal Act, marking the government’s clear-cut push to remove Native American tribes from east of the Mississippi River. The Indian Removal Act opened land that Indigenous peoples had previously called home to White settlement and the expansion of slavery, further codifying injustices at the federal level that had long been underway.

By the early 1800s, the U.S. federal government, and several state governments, had already frequently pushed Indigenous tribes farther and farther west. Violence, threats, deception, and legal agreements, often treaties, were tactics used to transfer Indigenous-held land to White people.

Though there was significant Native American resistance, many of these earlier efforts at ethnic cleansing were successful. These anti-Indigenous policies, coupled with the spread of diseases transmitted by settlers, had severely decreased the population of Indigenous peoples in North America. However, there was still a substantial Indigenous presence east of the Mississippi River.

Tribes living in what is now the U.S. Southeast at the time included the Cherokee, Choctaw, Chickasaw, Muscogee (Creek), and Seminole. By the 1800s, these nations were known collectively as the “Five Civilized Tribes” because they had adopted aspects of White, settler culture. Pressured by the U.S. government, many copied the ways settlers dressed, their educational system, their practice of Christianity, their use of plantation agriculture, and their enslavement of people of African descent. Originally, enslavement by Native Americans was not the same as that practiced by White settlers. Being enslaved was not an inherited or permanent status. The enslaved could be adopted into the family. This changed as the cultures and beliefs of these tribes became virtually identical to the United States. Still, the “civilized” practices of the five tribes did not stop the White settlers’ growing demands for their lands.

Two historic events, the Louisiana Purchase in 1803 and the War of 1812, sped this land grab. The Louisiana Purchase bought the U.S. government the exclusive right to purchase or forcibly take lands from various Indigenous governments. Lacking enough funds to pay veterans of the War of 1812, the U.S. government offered them land in what are now the states of Illinois, Michigan, and Arkansas — lands occupied by Indigenous peoples.

As in the Southeast, Native American tribes occupied huge swaths of what the U.S. called the Northwest Territory, now the U.S. states of Ohio, Indiana, Illinois, Michigan, and Wisconsin. An alliance of tribes from this region (including the Delaware, Potawatomi, and Shawnee) led by a war chief of the Miami tribe (Little Turtle) had resisted expansion and defeated U.S. forces in 1790 and 1791.

Many Native American nations likewise fought against U.S. expansion during the War of 1812, which pitted the United States against Great Britain. The Shawnee, Delaware, Miami, Potawatomi, and Creek, among other tribes allied for this purpose, under the leadership of Shawnee war leader Tecumseh. From the Ohio Valley, he envisioned a confederation of nations spanning from Canada to the Gulf of Mexico to fight against U.S. territorial expansion.

Similarly, the British wanted to stop U.S. expansion to protect its Canadian territory. To help in this effort, the British fought to keep the Great Lakes under Indigenous control. Thus, Tecumseh’s alliance joined the British in the fight against the United States during the War of 1812. British forces and the Native Americans provided each other with military support, supplies, and aid.

Tecumseh led an effective campaign against the U.S. invasion into Canada and the Northwest Territory, winning several victories, including at Fort Detroit. The Indigenous-British alliance largely fell apart with Tecumseh’s death in battle near Moraviantown, Ontario, Canada, in October 1813. Afterward, Native American military resistance was no longer strong enough to threaten U.S. forces in the region. However, this did not end Native American resistance in the Great Lakes or in other parts of North America.

A series of legal treaties, mostly after violence against Native American communities, preceded the 1830 Indian Removal Act. From 1814 to 1824, 11 treaties were signed that provided the legal framework to redistribute land from Southeastern Indigenous peoples to Whites. U.S. Army Officer Andrew Jackson helped negotiate nine of these treaties. From 1813 to 1814, Jackson fought alongside the Cherokee and the Lower Creeks against the Upper Creeks, known as the “Red Stick Creeks.” The Red Stick Creeks had allied with the British to maintain their more traditional culture. Jackson also invaded Spanish-controlled Florida to fight against the Seminoles for their role in helping enslaved people escape to freedom.

Jackson went on to serve as president of the United States from 1829 to 1837, promoting and signing the Indian Removal Act of 1830 into law. Not all members of Congress supported the Indian Removal Act. Tennessee Rep. Davy Crockett was a vocal opponent of the proposal.

Removal of eastern Native American peoples to west of the Mississippi River was intended to be voluntary. Some Native American communities complied. Others, including many in the nations of the Cherokee, Creek, Choctaw, Seminole, and Chickasaw of southeastern North America, did not take the deal to give up their lands to move west of the Mississippi River. The Cherokee, Creek, Choctaw, and Chickasaw tried to negotiate with White settlers and the U.S. government, offering some lands to remain in place.

Most of the Seminole Nation fought against their removal in what became known as the Second and Third Seminole wars. The Cherokee used the U.S. legal system to fight against their removal. Though they won their case in the Supreme Court, Jackson and the U.S. military did not honor that decision.

This forced removal, which occurred throughout the late 1830s, became known as the Trail of Tears. From 1827 to 1838 about 23,000 Creek people were forced into Indian Territory, thousands of whom died on the three-month journey.

In all, more than 46,000 to 60,000 Native Americans were forced—sometimes by the U.S. military—to abandon their homes and relocate to “Indian Territory,” which became the state of Oklahoma. This did not include several thousand more people of African descent, those who were enslaved and those who were not, nor did it include Whites married to Indigenous partners.

The Indian Removal Act marked the completion of ethnically cleansing Indigenous peoples from east of the Mississippi River. In the years that followed, subsequent federal policies would continue to uproot Indigenous peoples, clear the way for additional U.S. expansion, and remove Native peoples from their communities.

Today, the Trail of Tears is a National Historic Trail stretching from Tennessee to Oklahoma. It specifically chronicles the removal of the Cherokee from 1838 to 1839.