American Flamingos (Phoenicopterus ruber) are a cultural icon of Florida, USA, yet their status in Florida has been controversial for nearly a century. There is uncertainty regarding historical baselines and long-term trends in flamingo populations, whether flamingo nesting has occurred in Florida, and whether recent observations are wild birds or escapees from captive populations. We review historical and contemporary information to clarify the status and trends of flamingos in Florida and to lay a scientific foundation for their management. We compile historical information from early naturalists and museum records to describe historical abundance, distribution, and phenology. We show definitive evidence for 19th-century flamingo flocks numbering hundreds to thousands of individuals, with large flocks recorded through the year. Historical flocks were heavily hunted, and there is strong evidence that hunting led to extirpation of the historical population by ∼1900. One plausible description of nesting and 4 egg specimens apparently collected in Florida in the 1880s suggest that flamingos probably nested in Florida, though the evidence is not irrefutable. Citizen science data from 1950 to 2015 reveal directional population increases over this period. Contemporary observations reveal dispersal from a breeding colony in Yucatan, Mexico, to Florida, but no conclusive evidence is available for escapes into wild populations. Recent population increases in Florida are best explained by immigration from expanding nesting populations in the Caribbean, rather than increased numbers of escaped individuals. Resolving the long-standing controversy over the status and origin of Florida's flamingos will help develop appropriate evidence-based management strategies for this species—a culturally significant component of Florida's avifauna.