DebConf is the annual conference for Debian contributors and users interested in improving Debian. Previous Debian conferences have featured speakers and attendees from all around the world. DebConf17 took place in Montréal, Canada and was attended by 400 participants from 51 countries.
DebConf18 is taking place in August 2018 in Hsinchu, Taiwan from July 29th to August 5th, 2018.
They have opened CFP: https://debconf18.debconf.org/cfp/