This single-arm study will evaluate the efficacy and safety of peginterferon alfa-2a in treatment-naive Baltic participants with Hepatitis B envelope antigen (HBeAg)-positive chronic Hepatitis B virus (HBV). All participants will receive peginterferon alfa-2a 180 micrograms (mcg) subcutaneously once weekly. Following 48 weeks of treatment, there will be a 24 week period of treatment-free follow-up. The anticipated time on study treatment is 3-12 months, and the target sample size is less than 100 participants.