On to Paris, and then to London, where Trotsky finally met Lenin at a rooming house at 30 Holford Square, King's Cross. Trotsky was immediately appointed editor of The Spark, an underground Communist newspaper which was directed at Russian agitation. Trotsky also gave some Marxist lectures in London's predominantly Jewish White chapel district, and he took up with a Ukrainian (Gentile) woman, Natalya Ivanovna Sedova. Before long the two became lovers, and produced two male children.
http://www.redwatch.net/trotsky.html