Eritrea is not a member of the Hague Convention countries. Four main steps are needed to achieve the legalization of the Eritrean embassy. The apostille is the last step for all the countries participating in The Hague.
Eritrea is not a country in The Hague. For this reason, your document must also be certified by the U.S. Government and legalized by the Eritrean embassy.
So, if you have an Eritrea birth certificate that was issued in Eritrea and want to use in USA, you must send your birth certificate to Eritrea, obtain certification from the Eritrean Department of Foreign Affairs and legalize it at the USA Embassy in Eritrea. I am a US citizen and was born abroad in Eritrea.
Q: How can I get an apostille for my birth certificate that can be used in Mexico?
A: You must contact the U.S. Department of State Office of Vital Records in Washington, D.C. They issue you a certified birth certificate and then send it to the U.S. Department of State's Office of Authentication, to obtain the apostille for use in Mexico.