As of 2011, Argentina is the country with the fourth largest Spanish speaking population (approximately 40 million).
Could you be thinking of Mexico? It is the only spanish speaking country with a population over 100 million.
Mexico (2013 population estimate 117 million)
Mexico has the largest population among Spanish-speaking countries, with over 120 million people.
Spain, with about 45 million.
Mexico.
Yes. With a population of more than 120 million (2015), Mexico is considered the largest Spanish-speaking country in the world. It is followed by the United States with 52 million of speakers, Colombia (48 million) and Spain with 46 million.
According to Ask.com, "The United States, with a population of over 25 million Hispanics, is the fifth largest Spanish-speaking country in the world, after Mexico, Spain, Colombia, and Argentina."
The top 10 Spanish speaking countries are Mexico, Colombia, United States, Argentina, Spain, Peru, Venezuela, Chile Ecuador and Guatemala. Spanish is the second largest speaking language in the United States.
Mexico (2013 population estimate 117 million)
According to Ask.com, "The United States, with a population of over 25 million Hispanics, is the fifth largest Spanish-speaking country in the world, after Mexico, Spain, Colombia, and Argentina."
According to recent research conducted by one website, the smallest population of Spanish Speaker is Equatorial Guinea in Africa with approximately 616,459 inhabitants representing 0.14 % of the worldwide Spanish Speaking population. However, Spain is the only country that provides Spanish citizenship. There is only one "spanish country"-SPAIN if you mean spanish speaking country then I am not sure.