The declaration of sovereignty by Latvia's Supreme Council on May 4, 1990, emerged from growing discontent with Soviet governance and the desire for independence that permeated the Baltic region. Latvia, alongside its Baltic neighbors Estonia and Lithuania, had faced decades of Soviet occupation since World War II. Rising nationalism and calls for independence were fueled by the broader perestroika and glasnost reforms initiated by Soviet leader Mikhail Gorbachev in the 1980s. In this context, the new political atmosphere allowed for the surfacing of long-suppressed national sentiments within Latvia. With the backdrop of a significant independence movement, the Supreme Council's decision echoed the will of a populace eager to reclaim their national identity and self-governance.

The declaration affirmed Latvia's right to establish laws and governance independent of Soviet authority, thus dramatically altering the political landscape of the region. The Supreme Council also emphasized the importance of parliamentary democracy, human rights, and protections for ethnic minorities within the country. This declaration was not merely a formality; it ignited mass support among Latvians who rallied behind the call for independence, significantly affecting the momentum of national movements within Eastern Europe.

In response, the Soviet Union attempted to suppress this burgeoning nationalism, but by the time of Latvia's full declaration of independence on August 21, 1991, the Soviet grip was weakening. The proclamation in May was an essential stepping stone that galvanized public sentiment and international attention towards Latvia's plight, facilitating its eventual full sovereignty.