Use the Easy Search or click on Advanced Search next to the Go button to select sources you would like to search. Click on "What am I Searching?" to see a list of sources included in each category. For history topics, try Multi-Subject Resources, Arts & Humanities (includes history databases) and/or Social Sciences. Results will include resources in many databases!
This service is Google's method of searching the invisible web. To see the full text of many of these sources, you need to be "authenticated" as a legitimate UIUC user. Do so by searching for the source title on the A-Z list of electronic journals and newspapers. Also try the advanced search.
For those in the know, full-text means entire journal articles, so you get the whole story.