The Encyclopedia Americana was a general encyclopedia written in American English. It was the first general encyclopedia of any magnitude to be published in North America. Following the acquisition of Grolier in 2000, Scholastic took over production; in 2018, the Encyclopedia Americana was merged into the Scholastic GO! database.

The encyclopedia has more than 45,000 articles, most of them more than 500 words and many running to considerable length (the "United States" article is over 300,000 words). Americana is international in scope and is known for its detailed coverage of American and Canadian geography and history. The company's final print edition was released in 2006. At first, Lieber planned only an English-language translation of the 7th edition of the popular German encyclopedia Konversations-Lexikon, familiarly known as Brockhaus after its publisher Friedrich Arnold Brockhaus. However, as work on the new encyclopedia progressed, Lieber sought and added original articles by leading U.S. writers and intellectuals of the day. United States Supreme Court Justice Joseph Story, for instance, contributed more than 120 pages of legal material to the 1st edition. Hence, when the Americana began appearing some 165 years ago, it represented a hybrid of 2 cultures, German and American. Stoddart's work, however, is not connected to the earlier work by Lieber.

In 1902, a new, 16-volume Encyclopedia Americana was published under the editorial supervision of Scientific American magazine. The magazine's editor, Frederick Converse Beach, was editor-in-chief, assisted by hundreds of eminent scholars and authorities as consulting editors and article authors. Beach also expanded the encyclopedia's coverage, especially in the area of the physical and life sciences. Between 1903 and 1906 the publisher was R.S. Peale & Co. From 1906 through 1936, Encyclopedia Americana was published by the Americana Corporation, with the editorial support of Scientific American. The relationship with Scientific American was terminated in 1911. From 1907 to 1912, the encyclopedia was published as The Americana.

In 1918–20, the Americana Corporation published a new, International, 30-volume edition, with George Edwin Rines continuing as editor-in-chief. By the late1960s, Grolier's annual sales of Encyclopedia Americana and its sister publications under Grolier—The Book of Knowledge, the American Peoples Encyclopedia, the Book of Popular Science, and Lands and Peoples were over $181 million, and the company held a 30 percent market share as the leading publisher of encyclopedias in the United States. Grolier's corporate headquarters were in a large building (variously named the Americana Building and the Grolier Building) in Midtown Manhattan, at 575 Lexington Avenue. Sales during this period were accomplished primarily through mail-order and door-to-door operations. Telemarketing and third-party distribution of Encyclopedia Americana through Grolier's Lexicon Publications subsidiary added to sales volumes in the 1970s. By the late 1970s, Grolier had moved its operations to Danbury, Connecticut.

Later developments

In 1988, Grolier was purchased by the French media company Hachette, which owned a well-known French-language encyclopedia, the Hachette Encyclopedia. Hachette was later absorbed by the French conglomerate the Lagardère Group.

A CD-ROM version of the encyclopedia was published in 1995. Although the text and images were stored on separate disks, it was in keeping with the standards current at the time. More importantly, the work had been digitized, allowing for the release of an online version in 1997. Over the next few years, the product was augmented with additional features, functions, supplementary references, Internet links, and a current events journal. A redesigned interface and partly re-engineered product, featuring enhanced search capabilities and a first-ever ADA-compliant, text-only version for users with disabilities, was presented in 2002.

The acquisition of Grolier by Scholastic for US$400 million, took place in 2000. The new owners projected a 30% increase in operating income, although historically Grolier had experienced earnings of 7% to 8% on income. Following the acquisition, Americana became part of a suite of educational resources, with those resources including The New Book of Knowledge, The New Book of Popular Science, America the Beautiful, Grolier Multimedia Encyclopedia, Amazing Animals of the World, and Lands and People. All of those resources formed Grolier Online (now called Scholastic GO!). Staff reductions as a means of controlling costs also followed soon thereafter, even while an effort was made to augment the sales force. Cuts occurred every year between 2000 and 2007, leaving a much-depleted workforce to carry out the duties of maintaining a large encyclopedia database.

In 2004, Scholastic stated that Americanas 2,500 online articles are being revised annually.