We present deep polarimetric observations at 1420 MHz of the European Large Area ISO Survey North 1 region ( ELAIS N1 ) as part of the Dominion Radio Astrophysical Observatory Planck Deep Fields project . By combining closely spaced apertures synthesis fields , we image a region of 7.43 square degrees to a maximum sensitivity in Stokes Q and U of 78 \mu Jy beam ^ { -1 } , and detect 786 compact sources in Stokes I . Of these , 83 exhibit polarized emission . We find that the differential source counts ( \log N - \log p ) for polarized sources are nearly constant down to p > 500 \mu Jy , and that these faint polarized radio sources are more highly polarized than the strong source population . The median fractional polarization is 4.8 \pm 0.7 % for polarized sources with Stokes I flux density between 1 and 30 mJy ; approximately three times larger than sources with I > 100 mJy . The majority of the polarized sources have been identified with galaxies in the Spitzer Wide Area Infrared Extragalactic Survey ( SWIRE ) image of ELAIS N1 . Most of the galaxies occupy regions in the IRAC 5.8/3.6 \mu m vs . 8.0 / 4.5 \mu m color-color diagram associated with dusty AGNs , or with ellipticals with an aging stellar population . A few host galaxies have colors that suggests significant PAH emission in the near-infrared . A small fraction , 12 % , of the polarized sources are not detected in the SWIRE data . None of the polarized sources in our sample appears to be associated with an actively star-forming galaxy .