No ... 100 years is too many generations 'back'.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.
No this is not acceptable evidence to prove US citizenship. There are many requirements to prove citizenship in the US. Look at the USCIS website.
The answer provided here is general in nature and does not take into account other factors that may need to be reviewed for a more precise answer. You should consult with an immigration attorney before taking any action. The answer here is not intended to create an attorney-client relationship.
Perhaps. The following legal guide may answer some of your questions.
Mr. Shusterman's (former INS Trial Attorney, 1976-82) response to your question is general in nature, as not all the facts are known to him. You should retain an attorney experienced in immigration law to review all the facts in your case in order to receive advice specific to your case. Mr. Shusterman's statement above does not create an attorney/client relationship.
Being related (distantly or not) to someone who is (or was) a U.S. Citizen does not give you citizenship.
You can reach Colorado Legal Solutions by phone or email. Stephen Harkess is an attorney licensed in the state and federal courts of Colorado. This answer is for general information only and does not create an attorney client relationship between Stephen Harkess or Colorado Legal Solutions and any person. Sometimes free advice is only worth as much as you paid for it. You should schedule a consultation with an attorney to discuss the specifics of your legal issues.