The 1840 census asked for the names and ages of "Pensioners for Revolutionary or Military Services, Included in the Foregoing" Household. Pensioners included both veterans and widows. This clue should lead the researcher to Revolutionary War military service and pension records. The pension files, which are especially useful, have been reproduced online in NARA microfilm publication M804, Revolutionary War Pension and Bounty-Land Warrant Application Files.
The information included within this database includes the applicants name, age, town, county, and state, as well as the head of household with which the individual was enumerated in.