The tax system and the application of taxes are very important elements in the economic and social society of a country because taxes do not only fill the state or local treasury but can achieve a number of measures that can change the economic or social policy of a country. This has also been shown by examples throughout history that will be cited in this graduate thesis. Throughout history, taxes have changed so we can say that taxes are changeable and change according to the needs of the population of a country or the circumstances of a particular time. They are also a picture of society because we can see how economically strong and stable the state is but we can also see the poverty and shortcomings of a particular state in taxation. We have an example of income taxation in the Republic of Croatia where employers set aside an additional 40% on average in addition to the net salary for taxes and contributions, depending on the salary of workers, which is the result of lower contracted gross salaries. Through this graduate thesis I will present the tax system through the earliest history and the history of the tax system of the Republic of Croatia. I will list the types of taxes in the tax system in the Republic of Croatia and explain state, regional and common taxes. I will present the principles of taxation, changes in taxes throughout history and their impact on the population over the years.