Which U.S. Supreme Court case held that the Second Amendment is incorporated against the states?

Which U.S. Supreme Court case held that the Second Amendment is incorporated against the states? McDonald v. Chicago answered that question in 2010.

The case challenged Chicago’s strict handgun restrictions after the Court’s 2008 decision in District of Columbia v. Heller recognized an individual Second Amendment right to possess a firearm for lawful purposes such as self-defense. Heller applied to the federal enclave of Washington, D.C.; McDonald addressed state and local governments.

In a 5–4 decision, the Court held that the right recognized in Heller was fundamental and was enforceable against the states through the Fourteenth Amendment’s Due Process Clause. The ruling invalidated Chicago’s handgun ban and extended Second Amendment protection beyond federal jurisdictions.

United States v. Cruikshank had earlier held that the Second Amendment restricted the federal government, not the states, and therefore did not incorporate the right. Caetano concerned stun guns and did not establish incorporation. McDonald also did not make firearm regulation unconstitutional in every circumstance; later cases continued to address the scope of permissible regulations.