My friend Grgdai,  sorry to say that after reading your posting I  think you are completely confused, your logic  cross each other. In some place you try to justify something based on somelogic and in other place you cut those points by you own logic.

So dear friend, my conclusion is either you are confused (if you are honest) or you are trying to mislead.

Let me give you some hint point wise, for detail you can search on internet as I am here not to teach anybody, that is not my job. And I believe you are smart enough to do that.

1.  You said- Siddhartha Gautam was born in Lumbini but his knowledge 'buddha' was
born in Gaya. In any case I don't want to base my national pride on an
ambiguous thing like historic national boundaries. Nepal didn't even
exist at that time. Are we Nepalis so pathetic that we have to base our
national pride on someone who was born 3 thousand years ago when Nepal
didn't even exist and a mass of rock called mount everest that we had no
hand in building?

a) Kautilya arthasastra mentioned Nepal and rugs made in Nepal. Kautilyas period is 350-283 BCE, Buddha period was 563-483 BCE,  so Kautilya was born 133 yrs after the death of Buddha. So there is mention of a country called Nepal  (as Nepala) which was written approximately 160 yrs after the death of Buddha. It is most likely that Nepal might have existed at that time. You straightforwardly said that Nepal didn't existed at that time please give me a proof that it was so.

b) As far as I understand actually India didn't exist at that time I tried to search on the internet but was not able to find the existence of a country called India/Bharat at that time. Please give us a proof that country called India existed at that time. So why it is OK to say Buddha was born in India. Buddha was enlighten in Bodhgaya it was a part of Mauryan empire but at the time when Buddha got enlightened there was no Maurya empire, it was one of the Jana Parisad where Buddha got enlightened . But I have seen in another post that the knowledge Buddha was born in India so it is OK to say Buddha was born in India. According to your own logic Buddha was not born in India, then why are you putting counter argument on this? are you really honest with yourself?

My friend if you want to follow your own logic why don't you say knowledge Buddha was born in  jana parisad instead of India, It looks like you don't have problem when people say Buddha was born India, you invalid your own logic, be honest to yourself.

c) As pointed out by Geology Tiger here we are talking about the here we are talking about Siddartha Gautam who later became Buddha, so if you want to talk about the knowledge only, this is wrong thread you replied, my friend please don't get confused.

You said-His teachings show a lot of knowledge which are based on the obvious
which you could have figured out on your own but maybe never put into
words. This is basic reality but his teachings have made a profound
effect all over the world and he has a lot of followers all over
practicing different schools and off shoots of buddhism.

Yes you are right Buddha's teaching is based on obvious knowledge. When people find something which is already there it is called discovery, you seem to be a person of great logic then why don't you say Siddhartha Gautama "discovered" Buddhism.

You said: He gained his bodhisatwa in India

Same as above, as far I understand there was no country called India at that time. Buddha got enlightenment in one of the Janaparisad. Once  again following your own logic I can easily say Buddha  was not enlightened in India. If India existed at that time please tell me who was the ruler.

You claimed you are Buddhist: Good for you my friend, but please don't destroy Buddhism as some Islamic people destroying Islam in the name of Islam.