Saudi Arabia’s King Salman embarked on a landmark visit to Russia on 4 October, becoming the first Saudi monarch to visit the country. Cool relations are thawing as the two countries boost economic ties despite conflicting geopolitical agendas.

The increasing economic alignment of Russia and Saudi Arabia was brought clearly into focus by King Salman’s arrival in Russia on 4 October. Ten years after President Vladimir Putin became the first Russian president to visit the kingdom...