Gotama Buddha told his followers he was not the first Buddha, or awakened/self-aware being, to attempt to teach others about the nature of reality and to truly know oneself.
He also taught reincarnation is part of the natural order, as have most cultures since the beginning of this species, Indigenous Americans and many African cultures acknowledging it as the circle of life.
Therefore it is highly likely Gotama has reincarnated as a human since, being a Bodhisattva, a being who has fulfilled their karma and chooses to incarnate again in the Samsara cycle to continue to help others.
That also means he would have learned more about the ever-changing universe, including Earth, and developed new karma from new experiences and his teachings would probably have evolved, especially due to the insights uncovered by other beings who became wiser than he was, a goal of his and other wisdom teachers such as Socrates, Jesus Christ, Muhammad and Moses.
In that way Buddhism as a religion, or formal, static set of rules, doctrines and practices is irrelevant and can be, and has been, a hindrance to the further evolution of humanity. This is one reason he did not want to be regarded as a god to be worshipped and never to be questioned; in fact, he encouraged skepticism, explaining that blind faith is a hindrance, and to reach “nirvana,” those who followed his path would eventually need to abandon adherence and attachment to his teachings.
Humans, having been kept from awakening and truly knowing the Dharma, or the Truth, inevitably develop belief systems called religion to provide a structured framework to more easily discover who they are and can be. Because of the systems of stratification present in the times and locations of teachers like himself they alone lacked the power or time to completely uproot during their lifetimes, such belief systems were used as vehicles of suppression and domination by those who wish humans to not know themselves or the Truth, routinely using violence and manipulation to do so, creating more suffering and stagnation for humanity.
But if such structuref belief systems had never been established and adopted, cultural institutions and gathering places such as churches, temples, mosques and monasteries would have never become gathering places for like minded individuals to commute, share, learn from and love one another.
I was an atheist for most of my life, now 33 years old writing this. I was distraught by the ways in which religion and other conformist ways of living and thinking had led to the suffering of others and myself. This mentality was fortified as I developed as a journalist in high school and college, witnessing and writing about the ways in which humans used such belief systems to divide and hurt one another. But my innate insatiable curiosity led me to keep seeking truth, including to find out why I was so unhappy and conflicted, the causes of my suffering and the suffering of others.
That is not to say I have become or ever will be an individual who wholly adopts one of these rigid belief systems and accepts the status quo of the ways in which the organized forms perpetuate division and violence, much to the dismay of those who do in my family, social circle and the world.
But most of those upon which religions were founded also rejected the status quo of belief systems in their communities and lifetimes, and part of why they were persecuted or killed for it, and also regarded as heroes many worship or see as benevolent historical figures. If they had never taught others who also had an insatiable curiosity about themselves and reality, those individuals would have never come together and made connections that changed their lives and the lives of others, including the collaboration necessary to relay such teachings and stories orally or through written language, or in the case of The Bible, changing the course of human languages, including English, the most predominant way people interact now on Earth.
Gotama, Jesus, Muhammad and other teachers ultimately knew that those who seek to keep humans in bondage physically, intellectually and spiritually can only continue to retain such power if humans isolate, or never have opportunities to learn from one another, only coming together to harm and kill one another for land, scarce resources or the prevailing of one belief system or prevailing way of life.
In this way, religion is a messy inevitable compromise that has led to great suffering, but also greater levels of connection and unity. And now, in 2018, we have even more opportunities outside of those rigid belief systems for connection.
As I write this, there is a small gathering of people outside of the park I live next to holding cell phones to play the videogame Pokémon GO because the city park for children is a “Pokéstop” where players can collect characters who have “spawned” at those locations. All of them drove here to do so, and now relative strangers, or friends, with different belief systems and ways of life, have come together in one place to laugh, play and get to know each other, or to just be. Some of them may become friends and create the next tech company, non-profit or musical group to transform the world forever. Or perhaps just two of them will fall in love and give birth to a new spiritual leader, scientist or artist, to bring new teachings to help us better know ourselves and the nature of reality, and create a better world in which we can achieve greater levels of happiness and freedom.
Granted them doing so is only possible through using fossil fuels that compound environmental degradation, devices built by humans who are paid a slave wage in unsafe working conditions, made with materials that are harvested through mining the damages the health of the Earth, and increase the chances of the players hitting a pedestrian or other car and causing death and suffering on their way to the park, or when leaving it.
That does not mean we should disregard the negative consequences of such avenues of connection, like the violence and predatory domination organized religion can perpetuate, nor do we have to accept and allow belief systems, based on rules and doctrines that only made sense for people hundreds or thousands of years ago and are impractical now, to continue as is when they no longer serve us or hold us back from truly knowing ourselves and the Truth. Nor does it mean we must perpetuate religion to sustain a false sense of comfort for ourselves and our families through stratification and subjugation of others, as political and economic belief systems also do, often with the integration of organized religion to enforce them.
We cannot change the creation of such belief systems or the suffering they have brought in the past. But as long as we continue down the path of seeking connection, for which there are even greater opportunities because of the internet, especially fun forms like videogames or social media groups, we will naturally abandon organized, stagnant and rigid religions because we will have found less destructive and divisive means to connect.
Despite the suffering religion has created, it is ultimately unity and mutual co-operation that has been the most fundamental teaching of the individuals upon which such rigid belief systems were founded.