Melding classical and folk influences with lush vocals and acoustic instrumentation, Icelandic chamber pop outfit Árstíðir found immediate success upon the release of their chart-topping self-titled 2009 debut. Working without label support, they remained popular in their home country over the next few years, releasing a 2011 follow-up, then gaining international attention when a 2013 video of them singing an a cappella Icelandic hymn at a German train station went viral on YouTube. Subsequent releases like 2015's Hvel and 2018's Nivalis saw Árstíðir adding occasional rock and...