Noel, here's what Nichiren teaches about Shakyamuni Buddha

Question: Since the beginning of the kalpa of continuance, has anyone become enlightened to the lotus that is the entity of the Mystic Law? 

Answer: The Shakyamuni Buddha who lived in a past even more distant than gohyaku-jintengo became enlightened to the lotus that is the entity of the Mystic Law. Thereafter in age after age and lifetime after lifetime, he declared that he had attained the way and he revealed the fundamental principle of wisdom and reality (the deep merging or fusion of objective reality or truth and the subjective wisdom to realize that truth, or the Buddha-nature inherent within one's life). 

In our present world as well he appeared in the kingdom of Magadha in central India, intending to reveal this lotus of the Mystic Law. But the people lacked the proper capacity and the time was not right. Therefore he drew distinctions reguarding this lotus of the single Law and expounded it as three kinds of flowers, delivering to the people of the provisional teachings of the three vehicles. For over forty years he guided and led them with these temporary teachings according to their capacities. During this period, because the capacities of the persons he addressed were so varied, he bestowed upon them the various flowers and plants of the provisional teachings, but he never spoke of Myoho renge kyo. That is why, in the Muryogi Sutra, the Buddha said: "In the past I sat upright in the place of meditation[forsix years] under the Bodhi tree...In these more than forty years, I have not yet revealed the truth." 

But when he preached the Lotus Sutra, he cast aside the various plants and flowers of the Hinayana doctrines and the provisional teachings, which correspond to the expedient means of the four flavors and three teachings, and explained the unique doctrine of Myoho-renge. When he opened the three figurative lotuses to reveal the single lotus of Myoho renge, the people of the provisional teachings with their four flavors and three teachings were able to gain the lotus of the first of the ten stages of security. (stage of non-regression). Not until he revealed the lotus of 'opening the near and revealing the distant" were they able to obtain the lotus of the highest result, advancing to the second stage of security, the third stage of security, the tenth stage, the stage of near perfect enlightenment and finally, the highest stage of perfect enlightenment."(The Entity of the Mystic Law).