Draft version July 22, 2021 Typeset using L A T E X twocolumn style in AASTeX62 MALS SALT-NOT survey of MIR-selected powerful radio-bright AGN at 0 <z< 5 N. Gupta, 1 G. Shukla, 1 R. Srianand, 1 J-.K. Krogager, 2 P. Noterdaeme, 2 A. J. Baker, 3 F. Combes, 4 J. P. U. Fynbo, 5, 6 E. Momjian, 7 M. Hilton, 8 T. Hussain, 1 K. Moodley, 8 P. Petitjean, 2 H.-W. Chen, 9 P. Deka, 1 R. Dutta, 10 J. Jose, 11 G. I. G. J´ ozsa, 12, 13, 14 C. Kaski, 11 H.-R. Kl¨ ockner, 15 K. Knowles, 16 S. Sikhosana, 16 and J. Wagenveld 15 1 Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411 007, India 2 Institut d’Astrophysique de Paris, UMR 7095, CNRS-SU, 98bis bd Arago, 75014 Paris, France 3 Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854-8019, USA 4 Observatoire de Paris, Coll` ege de France, PSL University, Sorbonne University, CNRS, LERMA, Paris, France 5 Cosmic Dawn Center (DAWN), University of Copenhagen, Jagtvej 128, DK-2200, Copenhagen N, Denmark 6 Niels Bohr Institute, University of Copenhagen, Jagtvej 128, DK-2200, Copenhagen N, Denmark 7 National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801, USA 8 Astrophysics Research Centre and School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Durban 4041, South Africa 9 Department of Astronomy & Astrophysics, The University of Chicago, 5640 S Ellis Ave., Chicago, IL 60637, USA 10 Dipartimento di Fisica G. Occhialini, Universit` a degli Studi di Milano Bicocca, Piazza della Scienza 3, 20126 Milano, Italy 11 ThoughtWorks Technologies India Private Limited, Yerawada, Pune 411 006, India 12 South African Radio Astronomy Observatory, 2 Fir Street, Black River Park, Observatory 7925, South Africa 13 Department of Physics and Electronics, Rhodes University, P.O. Box 94, Makhanda, 6140, South Africa 14 Argelander-Institut f¨ ur Astronomie, Auf dem H¨ ugel 71, D-53121 Bonn, Germany 15 Max-Planck-Institut f¨ ur Radioastronomie, Auf dem H¨ ugel 69, D-53121 Bonn, Germany 16 Astrophysics Research Centre and School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Durban 4041, South Africa Submitted to ApJ ABSTRACT We present results of an optical spectroscopic survey using SALT and NOT to build a WISE mid- infrared color based, dust-unbiased sample of powerful radio-bright (>200 mJy at 1.4 GHz) AGN for the MeerKAT Absorption Line Survey (MALS). Our sample has 250 AGN (median z =1.8) showing emission lines, 26 with no emission lines, and 27 without optical counterparts. M1312-2026, the highest redshift object (z =5.068) in our sample, is the most radio-loud (R=1.4 × 10 4 ) AGN known at z> 5. Overall, our sample is fainter (Δi=0.6 mag) and redder (Δ(g - i)=0.2 mag) than radio-selected quasars, and representative of fainter quasar population detected in optical surveys. About 20% of the sources are narrow line AGN (NLAGN) – 65% of these, at z< 0.5 are galaxies without strong nuclear emission, and 10% at z> 1.9, have emission line ratios similar to radio galaxies. The farthest NLAGN in our sample is M1513-2524 (z em =3.132), and the largest (size∼330 kpc) is M0909-3133 (z em =0.884). We discuss in detail 110 AGN at 1.9 <z< 3.5. Despite representing the radio loudest quasars (median R=3685), their Eddington ratios are similar to the SDSS quasars having lower R. We detect 4 C iv BALQSOs, all among AGN with least R, and highest black hole masses and Eddington ratios. The BAL detection rate (4 +3 −2 %) is consistent with that seen in extremely powerful (L 1.4GHz > 10 25 W Hz −1 ) quasars. Using optical light-curves, radio polarization and γ -ray detections, we identify 7 high-probability BL Lacs. We also summarize the full MALS footprint to search for H i 21-cm and OH 18-cm lines at z< 2. Corresponding author: N. Gupta ngupta@iucaa.in arXiv:2107.09705v1 [astro-ph.GA] 20 Jul 2021