Arnolfo di Cambio
The Isaac Master, for his elevated technical level, is considered one of the first Italian Gothic painters, distant from the painters of his age. Much discussion has been held as to who the Master was. Some speculate that he was Gaddo di Zanobi Gaddi (due to similarity with Gaddi's work in Rome and Florence), while others say Pietro Cavallini, Arnolfo di Cambio, or Giotto.