1. They were old-school publishing houses, that had a connection to some prominent academic or an academic society that decided they needed to start a journal.

1. They were old-school publishing houses, that had a connection to some prominent academic or an academic society that decided they needed to start a journal. 2. The value proposition was that they were the only way to publish research. Libraries subscribed to them (or bought issues), and reading journals in a library was the major way academics learned of new research in their field, unless they learned of the research in a conference. 3. The Internet. 3b. The barriers to entry used to be needing to have access to a publishing house capable of duplicating issues, and having your journal be in major libraries (which is usually related to being related to a major academic or a academic society). The barrier to entry today is due to papers published being a major benchmark using which the productivity of an academic is measured. Older, well-known journals that accept only a few papers are known as having a larger "impact-factor", which means that publishing in them is worth more to an academic. 3c. The business model is always selling subscriptions to libraries, mostly university libraries (but also regular ones and research outfits in industry). Once they don't actually print anything their costs are mostly administrative, so they're basically printing money. The decision maker are librarians, usually, but they get set a budget by whoever owns the library. 4. Because they own the major benchmark used to evaluate an academic career. If you are an academic and want to further your career (i.e., get a job, get tenure, get a grant), you have to publish in one of those journals. If you're another academic and you then want to read that research, you then have to have your library subscribed to that journal (or look it up and Sci-Hub).