Mercury attracted inventive extractive industries as early as the twenty-first century. Getting to Mercury is difficult and requires a lot of fuel burnt to navigate the Sun's magnetic field. Getting away is easier, especially when employing solar sails that utilize our star's cosmic winds. Mercury does not have any settlements, but a number of mining and scientific operations.
Mining products leave the planet not by rocket but by mass accelerator, getting shot out towards the Terran and Venusian orbits in uncrewed cargo pods. Miners living on Mercury get paid well but live a hardscrabble life. Few stay for very long, if their finances allow it. Due to Mercury’s extreme conditions - during the day the planetary surface is directly exposed to the very close sun, getting bathed in extreme heat and radiation, during the night the lack of atmosphere sees the temperatures plummet towards absolute zero - all permanent installations on the planet are underground. Mercury's resources fueled the building boom in Earth's orbit in the last century before the Bracer War, and are currently in high demand for the expansion of the various projects on and around Venus.
Mercury is also a linchpin of inner system space traffic, since on average this celestial body is the closest planet to all other planets. This means Mercury’s orbit is one of the best policed places in the Inner System.
Mercury was the site of the Martian Civil War’s fiercest, and most protracted battle. Martian rebel operators captured one of the mining colonies, and effectively held the Mercurial orbit hostage. Corporate security forces farcast into the colony, and a weeks-long siege ensued. During the siege, several mining payloads were fired off from Mercury’s linear accelerators. One of these payloads hit the Lunar settlement of Boltzmann, obliterating it.