1893, Domingo Ghirardelli purchased the entire city block in order to make it into the headquarters of the Ghirardelli Chocolate Company. In the early 1960s, the Ghirardelli Chocolate Company was bought by the Golden Grain Macaroni Company which moved the headquarters off-site to San Leandro and put the square up for sale.

Ghirardelli Chocolate is the oldest continuously operating chocolate maker in the U.S. It was started by a man named Domingo Ghirardelli.Domingo Ghirardelli was an Italian immigrant. Growing up in Italy, his family introduced him to sugar-based treats early on in his life. He always had a fascination with them and later set out to start his own chocolate and candy company.He first tried his skills in Peru in South America. However, he relocated to California during the height of the gold rush. He originally sold sweet treats and drinks to the gold miners.A few years later he decided he wanted to open up a shop. In 1852, his dreams came true and he opened the first chocolate business in San Francisco. This business would later become known as the Ghirardelli Chocolate company we know today.

Ghirardelli Square

San Franciscan William M. Roth and his mother, Lurline Matson Roth, bought the land in 1962 to prevent the square from being replaced with an apartment building. The Roths hired landscape architect Lawrence Halprin and the firm Wurster, Bernardi & Emmons to convert the square and its historic brick structures to an integrated restaurant and retail complex, the first major adaptive re-use project in the United States.[citation needed] It opened in 1964. In 1965, Benjamin Thompson and Associates renovated the lower floor of the Clock Tower, keeping the existing architectural elements, for a Design Researchstore. The lower floors of the Clock Tower are now home to Ghirardelli Square's main chocolate shop.

Ghirardelli Square, considered the first successful adaptive reuse project in the country, has a history that spans more than a century and covers three continents. This specialty retail and dining complex, housing shops and restaurants, was originally a chocolate factory established by Domenico “Domingo” Ghirardelli.

Born in 1817 in Rapallo, Italy, Ghirardelli served as a Genoa confectioner's apprentice and at a young age developed a strong interest in the business. He left for Uruguay when he was 20 years old, then sailed around Cape Horn to Peru where he became a coffee and chocolate merchant.

James Lick—Ghirardelli's neighbor in Lima—left for San Francisco in January 1848 taking 600 pounds of Ghirardelli's chocolate with him. He arrived just thirteen days before the first shiploads of gold-rush pioneers. Lured by his friend's tales of the gold rush, Ghirardelli joined Lick a year later and opened a general store supplying mustard, coffee, spices and, of course, chocolate.

Between 1852 and 1895, Ghirardelli's Chocolate Factory was located at four different sites before the Ghirardelli Chocolate Company took over the Pioneer Woolen Mills on North Point Street—today's site of the Ghirardelli Chocolate Manufactory & Soda Fountain and Ghirardelli Square.

In the 1960s the chocolate manufacturing operation was sold and transferred to San Leandro. A group of San Franciscans, fearing Ghirardelli Square might be demolished, purchased the property. Unique shops and restaurants were created within the old factory, combining the latest in retailing and fine cuisine with the flavor of old San Francisco. The project officially opened on November 29, 1964.

Today, Ghirardelli delights visitors with its lively retail mix, while maintaining Ghirardelli's tradition as a trendsetter for the rest of the world. In 1982 the owners applied for and were granted National Historic Register status, a move that ensured the preservation of Ghirardelli Square for future generations.