A famed monster hunter and Cleric of Umera, Dr. Rudolph van Richten originally hailed from Cliffsunder in Commona, where he studied theology and magic at the Whiteharbour Academy. A devout student, he became an adventurer, and his work would often take him beyond the veil of the Prime Material. He gained a reputation as a hero of renown, a member of multiple famous adventuring parties, one of whom was the Theurge Ingrid Iskola. Rudolph and Ingrid bonded over their shared understanding life and devotion to the goddess Umyra, and eventually fell in love. They married, with Ingrid adopting van Richten's last name, and eventually had a child Erasmus van Richten.
Parenthood did not cease their desire to fight the Undead, and seeking action, the couple investigated when they heard of Dwarf Ghosts gathering around Copperbreach. After a perilous journey through the Snoutridge, tragedy fell on the van Richten family when Ingrid was overtaken by a ghost and thrown off a mountain peak; the cleric was too late to save her from possession as she fell into the mists below. Rudolph took care over Erasmus when his wife passed away, though he was unable to fully overcome his grief. Though he cared for Erasmus more than anything in the world, he became an uncompromising teacher, desperate to ensure that his boy would never make a similar mistake that Ingrid and he had made.
However, Rudolph's life again changed dramatically after after an incident occurred with a group of traveling Vistani. The band sought aid from Dr. van Richten to save one of their own, but the cleric was unable to raise the life of the young Vistana brought to him. In retribution, the Vistani stole Erasmus and sold him to the Vampire Baron Metus Syrek of Syrek-Kas. Rudolph chased them through the forests and mists, but was beset upon by a pack of Zombies led by an unknown Lich. Rather than killing him, the lich gave Rudolph control of the zombies as well as a ward against undead. He found the Vistani caravan and set the zombies on them, but before they died, their leader bestowed a Curse onto him: "Live you always among monsters, and see everyone you love die beneath their claws!"
Rudolph continued looking for his boy, interrogating Vistani about the group who had sold him. He eventually found his answer from the parents of Ezmerelda D'Avenir's and spared their lives, learning from them an entrance into Syrek-Kas through the Deepmists. In a few short months, Rudolph found Erasmus, but the boy had been made into a Vampire Spawn by the mad Baron. Erasmus begged him to end his curse, and Rudolph destroyed his son with a silvered sword. Overcome with rage and despair, Rudolph learned all he could about the Darklord and Syrek-kas. After learning of the vampire's proclivities, weaknesses, and oversights, van Richten slaid Baron Metus, then killed him by driving a stake through his coffin.
He began to live a life of solitude, always thinking about the curse, but as he aged, he came across a lone Vistana teenager. Ezmerelda had grown up troubled by the memory of what her family had done to van Richten, and ran away from home. After many harrowing adventures, she tracked him down, but thinking she was a Vistana assassin, Rudolph put a sword to her throat and threatened to spill her blood. Ezmerelda convinced him that she genuinely wanted to help him find his missing son, whereupon van Richten told her his sad tale.
Though he hated and feared the Vistani, and was worried about the truth of his curse, he took her in and taught her to defend herself as he had Erasmus. Dr. van Richten taught Ezmerelda on-and-off for ten further years, giving her access to Ingrid's old Spellbooks and teaching her to fight with a rapier. Ezmerelda was an apt student, graceful and skilled in Spellcraft, but the two fought constantly as van Richten's gruff demeanor and pragmatism chafed against Ez's natural optimism and self-sacrificing nature. His secret fear of his Vistani curse caused him to be far harsher with her than he had Erasmus, and as Ezmerelda grew to become a fine monster slayer herself, she found she could no longer work with him.
They had a long, irreconcilable argument on the responsibility of heroes. van Richten could not be swayed, as he knew far more loss than Ezmerelda had; eventually, the Vistana left in a huff, leaving the hard-headed old man alone. Now late in life, Rudolph was still dedicated to his craft, and learned of rumors of another domain guarded by mists, similar to Syrek-Kas. Knowing that he would likely fail with his weakened body, he nonetheless willed himself to enter Barovia with the intent to kill the Vampire Lord Strahd von Zarovich. He left Ezmerelda a note of apology in their previous home, packed the last of his things, and headed for the Sea of Clouds to find his way into the Shadowfell.
van Richten entered knowing that it would likely be the death of him, and made sure to enter the domain in disguise. From Wistimere's Marvelous Menagerie, he purchased a Capuchin Monkey named Piccolo and an unnamed Saber-Toothed Tiger. He adopted fake sharp ears and the alias "Rictavio", a Half-Elf Bard and entertainer who had become lost in the mists. Their cart was towed by his loyal steed Drusilla, and for the last time, the Doctor re-entered the Plane of Shadow.
Rictavio took up residence in the Blue Water Inn in Vallaki, telling wondrous stories of adventure in exchange for coin, and made connections throughout the town. Richer than most Barovians, he bartered with Urwin Martikov to allow him to stay at the inn, and he used his daylight hours to collect information on Strahd and his domain. He paid Gunther Arasek to allow him to keep his carnival wagon at the Arasek Stockyard, and after months of unpleasant shit-slinging, gave Piccolo to the depressed toymaker Gadof Blinsky.