Complex sentence: His work fell out of favour after the Second World War and at the time of his death he had slipped into obscurity, with only a handful of mourners at his funeral, held at Golders Green crematorium.
Split into simpler sentences: His work fell out of favour after the Second World War. At the time of his death he had slipped into obscurity, with only a handful of mourners at his funeral, held at Golders Green crematorium.