We present a multiwavelength study of the unidentified Fermi \gamma -ray source 0FGL J1830.3+0617 , which exhibits variability above 200 MeV on timescales of days to weeks .
Within the Fermi 95 % confidence error contour lies B1827+0617 , a radio source with spectral index \alpha = 0.09 between 1.4 and 4.85 GHz .
The flat spectral index and flux density of 443 mJy at 4.85 GHz are consistent with the bulk of Fermi sources associated with blazars .
It is also detected in the 0.3 - 10 keV band by Swift .
Optical imaging in 2009 May identifies B1827+0617 at R \approx 16.9 , and shows that it is at least 2 magnitudes brighter than on the Palomar Sky Survey plates .
Contemporaneous optical spectroscopy acquired during this high state finds a weak emission line that we attribute to Mg ii \lambda 2798 at redshift z = 0.75 , supporting a flat spectrum radio quasar ( FSRQ ) classification .
The variability characteristics and radio properties together indicate that 0FGL J1830.3+0617 at Galactic latitude b = +7. ^ { \circ } 5 is a blazar .
Blazar identifications of three additional low-latitude Fermi sources , 0FGL J0643.2+0858 , 0FGL J1326.6 - 5302 , and 0FGL J1328.8 - 5604 , are also suggested .