The evolution and population dynamics of avian coronaviruses (Av. CoVs) remain underexplored. In the present study, in-depth phylogenetic and Bayesian phylogeographic studies were conducted to investigate the evolutionary dynamics of Av. CoVs detected in wild and synanthropic birds. A total of 500 samples, including tracheal and cloacal swabs collected from 312 wild birds belonging to 42 species, were analysed using molecular assays. A total of 65 samples (13%) from 22 bird species were positive for Av. CoV. Molecular evolution analyses revealed that the sequences from samples collected in Brazil did not cluster with any of the Av. CoV S1 gene sequences deposited in the Gen. Bank database. Bayesian framework analysis estimated an Av. CoV strain from Sweden (1999) as the most recent common ancestor of the Av. CoVs detected in this study. Furthermore, the analysis inferred an increase in the Av. CoV dynamic demographic population in different wild and synanthropic bird species, suggesting that birds may be potential new hosts responsible for spreading this virus.