Glendale has one of the largest communities of Armenian descent in the United States.

Armenian families have lived in the city since the 1920s, but the surge in immigration escalated in the 1970s. Armenian Americans are well integrated into the city, with many businesses, several Armenian schools, and ethnic/cultural organizations serving this ethnic group. Most of the Armenians in Glendale arrived in the past two decades. The city of Glendale is home to one of the largest Armenian communities outside of Armenia.

Beginning in the late 1980s, with assistance from family and friends already there, Armenians from the former Soviet Union began arriving. In the Glendale Unified School District, by 1988, along with students from the Middle East, they had become the largest ethnic group in the public schools, now having a larger number than the Latinos. Glendale became the municipality with the largest number of ethnic Armenians outside of Yerevan, Armenia. In 2014, a Glendale Police Department spokesperson, stated, "In five to eight years, the [Armenian] community went from a few thousand to about 40,000." Levon Marashlian, an instructor of Armenian history at Glendale College, stated that in the early 1990s Glendale's Armenian community became the largest in the Los Angeles metropolitan area, surpassing the Armenian community of Hollywood. Alice Petrossian, the GUSD director of intercultural education, stated that Burbank lies within the middle of other Armenian communities, so it attracted Armenians. There are also a great number of Armenian immigrants from Iran who, due to the religious restrictions and lifestyle limitations of the Islamic government, immigrated to the US, many to Glendale since it was where their relatives resided.

A new headquarters of the Armenian National Committee/Western Region opened in 1994. By 1999, about 25% of the population spoke Armenian and there were many Armenian businesses. By 2005 the Armenian population was 40% of the total population.

According to the United States 2000 Census, Glendale is home to 65,343 Armenian Americans (making up 34.1% of the total population), increasing from 1990 when there were 31,402 Armenian-Americans in the city. As of 2005, one-third of Los Angeles' estimated 153,000 Armenians (or 51,000, around a quarter of Glendale's 205,000 residents) lived in Glendale. At that time, Armenians held a majority on the Glendale city council, and it had done so since that year.

As of March 2018, four of the five members of Glendale's city council are of Armenian descent: Mayor Vartan Gharapetian and councilmembers Zareh Sinanyan (mayor from 2014 to 2015), Ara Najarian (mayor from 2007 to 2008, 2010 to 2011, and 2015 to 2016), and Vrej Agajanian. Former Armenian American mayors of Glendale include Larry Zarian, Bob Yousefian, and Rafi Manoukian.

Singer Serj Tankian and bassist Shavo Odadjian, members of the Armenian American rock band System of a Down, were based in Glendale at the time of formation.

The Cathedral of Saint Gregory the Illuminator, which is the seat of North American diocese of the Armenian Catholic Church, is located in Glendale. The Bishop of the Diocese, Rt. Rev. Mikaël Antoine Mouradian, is also resident in Glendale.