Vega
Vega, also designated α Lyrae (Latinised to Alpha Lyrae, abbreviated Alpha Lyr or α Lyr), is the brightest star in the constellation of Lyra, the fifth-brightest star in the night sky, and the second-brightest star in the northern celestial hemisphere, after Arcturus. It is relatively close at only 25 light-years from the Sun, and, together with Arcturus and Sirius, one of the most luminous stars in the Sun's neighborhood.
Historical brightest stars
Working out exactly which stars were or will be the brightest at any given point in the past or future is difficult since it requires precise 3D proper motions of large numbers of stars and precise distances. This information only started to become available with the 1997 Hipparcos data release. Jocelyn Tomkin used this data to compile a list of brightest star in Earth's night sky at each period within the last or next 5 million years. Reanalysis of the Hipparcos data and new data from Gaia have rendered the list somewhat outdated. For example it doesn't include Gliese 710 which in about 1.35 million years time is expected to be close enough to have a magnitude of -2.7.