American history

ArchiveGrid provides more than 7 million records "describing archival materials, bringing together information about historical documents, personal papers, family histories, and more," from 1,400 archival institutions mainly from the US but with some international coverage. Finding aids include linked cross-references by subject heading, genre, personal names, groups, and places. Records also provide maps and contact information to make arrangements for examining the collections in person or, occasionally, online.

Social Explorer focuses on representing patterns in historical demographics of the United States since the first census in 1790. International coverage has less historical depth but includes recent census data from Canada and the UK, EuroStat's European Statistics, and the World Bank's World Development Indicators. The easy-to-use web interface lets users create maps and tables to illustrate, analyze, and understand demography and social change. In addition to its comprehensive data resources, Social Explorer offers features and tools to meet the needs of demography experts and novices alike.
Complements the broader but recent US coverage in PolicyMap for social policy and the US and Canadian coverage in SimplyAnalytics for business.

the Library of Virginia’s initiative to get documents into classrooms. Using primary sources, teachers can make history relevant to students while helping them learn and understand state standards. DBVa will teach students to be critical thinkers as they analyze the original documents and draw their own conclusions about Virginia’s past.

indexes finding aids (collection descriptions) to manuscripts and archival materials held by libraries across Virginia. These finding aids may link to digitized versions of these materials, but the majority of these collections have not been digitized, requiring researchers to go to the respective repositories.. 1607-present.

Complementing the better-known JSTOR with a more international orientation, PAO is a archive of more than 700 periodicals in the humanities and social sciences since their first issues. More than 150 are in languages other than English. Coverage is from volume 1, issue 1 of each journal, and all issues are digitized from cover to cover.

JSTOR (from Journal STORage) is an archive of academic journals in the humanities, social science, and sciences, from earliest issues up to 3-6 years before present. So for some purposes, it is a collection of secondary sources and for others, primary sources.
If you want to do a comprehensive, up-to-date search of the literature on a topic, don't begin in JSTOR; start in a discipline-specific database instead. JSTOR articles are exact facsimiles of originally as originally printed: they will include information may be obsolete and may use words that have shifted meaning and/or have become regarded as inappropriate, incomplete, or worse. But if you want to know what scholars in, say, the 1930s said about controversial topics like race, some religious traditions, gender and sexuality, or mental or physical impairments, you will need to use search terms that match words of that time, not ours, even though they may offend you deeply.

Portal to citations in American and British periodical indexes from the "long" 19th century. Search individually or cross-search with several governmental and book indexes. Tech won't necessarily have online or physical access to every indexed item.