ISC was founded by the Williams brothers Samuel, Nathaniel and Matthew on the grounds of the 4,428 acre Oakland Plantation. Samuel May Williams, who became secretary to Stephen F. Austin, raised money to support the war of independence against Mexico, and as partial payment for his services, he was granted land in 1840. Mule-powered mills were built to grind sugar cane and squeeze the sweet juice from the cane stalks to make syrup. Cane juice was boiled in large cast-iron kettles set up under covered sheds. In 1843, the Williams’ sugar crop on Oakland Plantation and the crops of other nearby farms were large enough to justify a commercial raw sugar mill on the property. The mill became the birthplace of ISC.
Upon Matthew Williams’ death in 1853, the plantation is sold to Benjamin F. Terry and William J. Kyle. They changed the name to the Sugar Land Plantation and began buying up adjoining plantations. Within five years, their 12,500 acre Sugar Land Plantation was one of the largest in Texas.
Production of sugar declined during the Civil War and most of the mills became badly run down. In 1864, William Kyle died. During the difficult 1870s and early 1880s, Kyle and Terry heirs managed to hold the Sugar Land plantation together, but soon the challenge became too difficult and in 1882, heirs of both families began selling off portions of the plantation to Col. Edward H. Cunningham of San Antonio. He, along with Col. Littleberry Ellis, purchased many of the faltering plantations at auctions, including the Kyle and Terry plantation.
Cunningham and Ellis entred into a partnership in 1875 and grouped the plantations together, invested over $1 million in new buildings and machinery and built another raw sugar mill called the “Imperial” mill. Less than a year after the new mill was built, their partnership was amicably dissolved. Cunningham retained the Cunningham Mill and some 12,500 acres of land, including the town of Sugar Land. He added facilities for processing the raw sugar and built a sugar refinery.
By 1902, Cunningham was older and not in good health. His plantations, mill and refinery were deteriorating, he was unable to meet payments, and his company was placed in the hands of a receiver.
W. T. Eldridge saw an opportunity to acquire the entire property under favorable terms. He approached I.H. Kempner of Galveston in 1907 with a proposal to acquire the raw sugar mill, refinery and all of the land in the area. Kempner and Eldridge became equal owners of the Sugar Land properties. Dan Kempner, one of Isaac's younger brothers, served as the new company's first president until 1914, when he was replaced by Isaac. As part of the Kempner-Eldridge agreement, Eldridge moved to the site to serve as general manager and build the company-owned town of Sugar Land. He was given the Sugar Land Railway.
In 1908 the Kempner Eldridge partnership acquired the adjoining 12,500-acre Cunningham Plantation with its raw sugar mill and sugar cane refinery and the name was changed to Imperial Sugar Company. The name “Imperial” arose because one of the raw sugar mills had been known as the “Imperial Mill” for a number of years. Kempner liked the name, as he had long been an admirer of the splendid Imperial Hotel in New York City, which he had visited as a young man. The hotel’s grandeur and unmistakable hallmark of quality had deeply impressed him. The hotel’s stationery had been decorated with a regal-looking crown so the name became “Imperial” and its symbol, a crown.
The newly founded town of Sugar Land attracted a stable population largely made up of German and Czech immigrants. As craftsmen and sugar experts arrived, the Imperial Sugar refinery was rehabilitated and launched on year- round operations using raw sugar imported through the Port of Galveston. ISC set up a support system for employees including building 500 new homes, providing medical care, and establishing the Imperial State Bank, the Imperial Mercantile Company, a company store, various retail stores, a cotton gin as well as feed and paper mills. ISC also paid for graveled streets with concrete curbs, gutters and sidewalks, a modern hospital and school system, as well as churches. The company furnished electricity, gas and water to the town.
After 1912, the production of raw sugar in the four-county area began to decline and ISC began to import raw sugar from Cuba in increasing quantities. In 1914, the company’s refining capacity was 525,000 pounds a day. At the end of 1915, and following expansions of the plant, capacity had been increased to 750,000 pounds a day. In 1924 the company was reorganized as a $5 million corporation. In 1925, ground was broken for an immense "Char House” 一 a structure of steel, concrete and bricks rising to a height of 150 feet and costing $1 million.
By 1932 ISC was the only remaining sugar manufacturer left in Texas and was struggling due to the Great Depression and an unsuccessful foray in fig processing. The combination of Eldridge’s death and the inability to purchase equipment and supplies due to wartime demand made it impossible to improve or maintain the refinery equipment. ISC survived only with the help of a loan from the Reconstruction Finance Corporation.
World War II brought the suspension of quotas under the Sugar Act and allowed unlimited imports. Under sugar rationing and other government wartime restrictions, ISC provided all the sugar for Texas and Oklahoma, an arrangement that resulted in the company's postwar dominance of the market in those states.
In 1946 the Kempner family bought out the remaining Eldridge heirs and became almost 100 percent owners of ISC, the lands around Sugar Land and the numerous corporate enterprises in the Sugar Land area. In 1948, I.H. Kempner’s youngest son, I.H. Kempner Jr., was made president and launched the company on a program of modernization. Soon, ISC was producing sugar on a 24-hour basis. In 1953 I.H. Kempner Jr. died and his two sons, I.H. Kempner III and James C. Kempner, stepped in to take over. Isaac Kempner's youngest son, Herbert, served as company president from 1948 until his death in 1953, when he was succeeded by W. H. Louviere, the first man from outside the family to hold the office.
In the 1950’s ISC opened the Sugar Land Shopping Center to house new executive offices and completed an innovative air-conditioned packing room. ISC’s output exceeded two million pounds of sugar daily. Bulk raw sugar supplies increased when the company sold a significant portion of its stock to the C and H Sugar Refining Company of California and Hawaii in 1956; ISC bought the stock back in 1967.
ISC acquired the Holly Sugar Corporation, a company formed from eight beet sugar processing plants, to form the Imperial Holly Corporation, a processor of both cane and beet sugar. With that acquisition, ISC more than doubled in size and became a marketer of both cane and beet sugar. After the merger, 60 percent of the company belonged to the Kempner family, 10 percent to an Employee Stock Ownership Plan, and 30 percent to public stockholders.
In 1996 ISC acquired Spreckels Sugar Company of California, a West Coast beet sugar company. In 1997, ISC acquired Savannah Foods & Industries, Inc., headquartered in Savannah, Georgia, which at the time was the second largest sugar refiner in the industry. Savannah Foods & Industries marketed its sugar under the Dixie Crystals® brand. Another legacy company, Savannah Foods was founded in 1915 by Benjamin Alexander Oxnard and Richard H. Sprague when they moved their entire sugar refining operation, including more than 300 employees and their families, from St. Mary’s Parish in Louisiana to Port Wentworth, Georgia. The Savannah Sugar Refinery began melting sugar on July 7, 1917.
As was the case with the Holly acquisition, the Company again more than doubled in size, becoming the largest processor and refiner of sugar in the U.S. Savannah’s two plants – Port Wentworth, Georgia and Gramercy, Louisiana became ISC’s main processing facilities.
Savannah Foods & Industries, Inc. had acquired Michigan Sugar, a beet sugar producer in Saginaw, Michigan in 1984, Great Lakes Sugar, in 1985 and Colonial Sugar Refinery located in Gramercy, Louisiana in 1986. The acquisition of Savannah Foods made Imperial Holly the first truly national sugar refiner and marketer in the country.
ISC filed for Chapter 11, due to lower sales for refined sugar and higher energy costs and it emerged from bankruptcy on August 29, 2001. In 2002 Imperial Holly sold Michigan Sugar Company and its Worland, Wyoming beet facility to grower cooperatives and its Rocky Mountain beet facilities to American Crystal Sugar Company. Upon the sale of these two entities, Imperial Holly became Imperial Sugar Company.
The original sugar refinery in Sugar Land was closed, however corporate offices still remain in the founding city.
Two buildings on the Sugar Land factory property were imploded by developers in order accommodate future redevelopment plans including residences, business properties and a community park. Also, ISC contributed its Gramercy, Louisiana refinery to Louisiana Sugar Refiners, LLC (LSR) in exchange for a one-third interest in the new company. LSR commenced operations on January 1, 2011.
Cargill and Sugar Growers and Refiners, Inc., (SUGAR) each have a 50% interest in the million-ton-per-year sugar refinery, after the two companies acquired all of Imperial Sugar's interest in LSR.
ISC was acquired by Louis Dreyfus Company, a global merchandiser of commodities, a major asset owner and a processor of agricultural goods with over 160 years of experience. As part of the Louis Dreyfus Company Group portfolio ISC again becomes one of the top three global sugar merchandisers and one of the largest cane sugar refiners worldwide.