Baccano! from the 1700s

Aboard the Advenna Avis in 1711, a group of alchemists summon a demon in the hopes of gaining eternal life. The demon gives them an elixir of immortality and the method of ending their existence by "devouring" one another. Soon after, one among them begins to devour his companions. Realizing the danger posed by staying together, they scatter across the globe. Centuries later in 1930's America, a certain federal investigator tries his best to combat the rise of organized crime during Prohibition, send a particularly infuriating terrorist to Alcatraz, and catch an outrageous thief duo. Meanwhile, the transcontinental train, the Flying Pussyfoot, begins its trail of blood across the country. In 2002, a small group of the original Advenna Avis alchemists are on a journey to find the rest of their fellow immortals. However, there is one companion they did not expect to meet again. Seemingly unrelated events, from a sleepy Italian city in the early 1700's to a modern luxury cruise ship traveling across the Pacific, reveal themselves to be far more connected than anyone could imagine... (Source: Wikipedia & MAL Rewrite)

New York, 1927. In a corrupt city where crime rules the streets, Firo Prochainezo is in the Camorra, an Italian criminal syndicate distinct from the mafia. Though a member of the relatively small Martillo family, Firo has big ambitions and is determined to make his mark. But while the Martillos may not be the biggest bad guys on the block, they've got some distinct advantages working in their favor. Does Firo have what it takes to become a made man? Let the crazy ruckus begin! (Source: Yen Press)