Read the announcement and docs for the DOC 2.0 API while evaluating news search options. It is free and needs no key, but it only searches the last three months. The requirement was eighteen months of press coverage, so I did not choose it as the main source.
- What worked
- No account is needed, and the docs explain the query model clearly.
- What got in the way
- The three-month search window makes it a poor fit for checking a longer history.