Trade between Mars and Venus creates trade routes…and piracy. The “pirate period” lasts 80 years before a new energy source helps Vectors develop ship-based weaponry. The foundation of the Inner Ring Police Force. While this is the dawn of the era of interplanetary travel, it’s something of a dark age.
Reference: Venus history from HSD 2.0
Date Notes: This has to be the single hardest date range to pin down. The Age of Piracy lasts 80 years, but there’s no really solid begin or end date, and ASR’s development of the Thrust Drive is tied into a lot of events as well but without a strong date to begin on. My first version of HSDs’s history had like 50 years of wiggle room on this date, there were so many hazy connections. This is my best guess and it’s still problematic. HSD2.0p.31 suggests more like 280, before 300/after Progenitus, but the pirate period would need to be more like 120 years, not 80)