What is the Free Navy in The Expanse season 5? While the Rocinante dealt with chaos on Ilus, the Sol system was busy learning the name "Marco Inaros" in The Expanse season 4. Inaros was already on the radars of Earth and Mars due to his long-standing status as an extremist member of the OPA (Outer Planets Alliance), but after peace was attained, Marco resurfaced, slaughtering the Earth colonists of the U.N. Soujourner ship on their journey through the Ring Gate. While Marco was taken into custody by Klaes Ashford, the villain's influence proved more far-reaching than anyone assumed. Inaros broke free, killed Ashford, and launched a deadly attack on Earth, announcing himself as the big new villain of The Expanse.

The first trailer for The Expanse season 5 is entirely built around Marco and his system-wide announcement of the Free Navy's arrival. Footage shows everyone from James Holden to Chrisjen Avasarala watching the transmission in which Marco declares himself the Commander of the Free Navy, promising to finally lead The Belt to prominence over the Inner Planets of Earth and Mars. Despite being relative newcomers, the Free Navy are well-armed and well-resourced, with Avasarala admitting that an all-out attack would likely fail. But in the ever-expanding world of The Expanse, what separates the Free Navy from the various other factions?

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The Free Navy is essentially a militarized evolution of the OPA's terrorist elements. While there was always an aggressive contingent within the OPA, the group were not inherently violent, established simply to represent the rights of Belters. However, the Belt was always too divided to become a true force against the Inners. The various factions rarely saw eye-to-eye, and power struggles between peaceful figures like Fred Johnson and subversive types such as Anderson Dawes ensured division was ever-present. The Free Navy, however, is a coalition of Belters from across the system, and their sole purpose is to take direct action against Earth and Mars, establishing the Belt as a dominant force.

Keon Alexander as Marco Inaros in The Expanse

The unity of Free Navy is one of several reasons they pose such a threat. Historically, the disorganized and disjointed nature of the OPA worked in the favor of Earth and Mars. Inaros provides a central figure for various factions to rally around, immediately providing strength in numbers. But the Free Navy also boast deep, illicit connections within the Martian government. Although The Expanse has yet to reveal any specifics, Bobbie Draper found Martian officials supplying weapons to the Free Navy's Filip Inaros. This solves another problem Belters have faced traditionally - being outgunned. The Martian military was once the strongest in the system, and now Marco Inaros is in possession of those weapons. Combined with his loyal followers, and it's easy to see why the Free Navy pose such a formidable threat.

Ever the opportunist, Marco Inaros used timing to his advantage in establishing the Free Navy, exploiting two major events to further his aims. In The Expanse season 3, Fred Johnson struck a deal with the Inners and created a tenuous peace for the Belt but, predictably, some viewed this as a betrayal of OPA values. Marco Inaros has galvanized this anger to fuel to Free Navy, but only thanks to another major event - the construction of the Ring Gate. When pathways to other parts of the galaxy opened up, Belters spotted an opportunity for a better life, but the Inners began patrolling the entrance, handing Belters a legitimate grievance and propping up Marco's narrative that Earth and Mars were still determined to oppress the Belters. In a serendipitous turn, the Ring Gate also bred dissension on Mars, allowing the Free Navy to strike a clandestine deal with the Red Planet. Thanks to a mixture of opportunism, circumstance, charisma, and strategic intelligence, the Free Navy have emerged as a dangerous enemy in The Expanse season 5.

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