On Easter Sunday, Google is honoring the birthday of the late labor organizer Cesar Chavez by placing a Chavez portrait within the middle “o” of the Google logo that appears on the homepage of the popular search engine.

While Google frequently decorates its logo to celebrate various holidays and special events, it is unclear why the company chose specifically to honor Chavez’s birthday, instead of Easter Sunday.

Chavez co-founded the organization now known as the United Farm Workers union (UFW). He became an iconic figure in the labor movement, with his stature only increasing since his death in 1993.

President Barack Obama released a statement in 2011 proclaiming March 31 “Cesar Chavez Day,” declaring, “I call upon all Americans to observe this day with appropriate service, community, and educational programs to honor Cesar Chavez’s enduring legacy.”

Google executive chairman Eric Schmidt was an informal adviser to both of President Obama’s presidential campaigns, a member of the Obama White House transition team in 2009 and a onetime prospect for an Obama Cabinet post during the president’s second term.

As The Daily Caller has reported, Schmidt is also a steadfast climate-change activist, and has advocated for the complete termination of the oil, natural gas, and coal industries, and predicted that Washington, D.C. will soon be completely underwater due to climate change. (RELATED: Schmidt’s influence in the Obama White House)

Conservatives on Twitter have reacted angrily to Google’s Chavez tribute.

Watch:

Follow Patrick on Twitter