During their reign they supported each other effectively in accordance to his joint motto of equality: "Tanto monta (or monta tanto), Isabel como Fernando", ("They amount to the same, Isabel and Ferdinand").
Selama masa pemerintahan mereka, mereka saling mendukung secara efektif sesuai dengan semboyan bersama tentang kesetaraan: "Tanto monta (or monta tanto), Isabel como Fernando", ("Jumlahnya sama, Isabel dan Ferrando").