Electronic Government (E-government) refers to the simplification and the transaction of business processes by the use of Information and Communication Technology (ICT), such as the Internet, to improve public service delivery. The implementation of E-government differs from country to country and is associated with a number of challenges for public administrators. Cloud computing is widely proposed as a solution to enhance the development of E-government. Previously, we have conducted a Systematic Literature Review (SLR) to identify essential factors that influence the adoption of cloud computing for E-government implementation in developing countries. In this paper, we present a quantitative study involving 234 IT experts to confirm the significance of the identified factors. SPSS along with AMOS is employed to analyze the data. Confirmatory factor analysis, measurement model and structural model are executed. Findings indicate that the following factors significantly influence the adoption of cloud computing for E-government implementation in Iraq: complexity, compatibility, top management support, relative advantage, IT knowledge and security. The results show that trust and technology readiness have no significant influence on E-government implementation via cloud computing. On a wider perspective, non-technological factors require more attention than technological factors. This review will be useful to decision makers in governments and public sectors that intend to leverage cloud computing to overcome the challenges they face in implementing e-Government successfully.